Because Business Insider is my go to source for all things photographic.
Actually I do like to sometimes put on a prime lens and go out and shoot. It’s my favorite for street photography and I think it’s a good exercise to do on occasion because it does make you move around and you learn to “see” better, but I wouldn’t want that to be my only option. Back in my film days that is all I had. Fuji 35mm with a 50mm lens, everything manual. I loved that camera but I’m never going back. The OP stated that his wife does everything in camera and no PP after the fact. She’s gonna want the ability to “crop” in camera and shooting with a fixed lens makes that difficult.

3 pages and no-one suggests what is to me the obvious answer - take her into a camera shop and let her choose! She sounds a bit like my wife who knows absolutely nothing about photography but takes great pics. She (my wife) wants a small camera, with a viewfinder, that fits into her bag/pocket. The one she has is a Lumix TZ70 and even though it has a 30x zoom she will shuffle backwards and forwards framing her subject. "Why not zoom" I sometimes ask only to be completely ignored as if the question is not worth answering. Then again sometimes I will be answered with words such as "you call yourself a photographer and you ask questions like that!" mmmmm.

You didn't state what DSLR gear you're using, so I looked at your earlier posts and see that in the past you had a 6MP Canon 300D (original "Digital Rebel", 2004 or so). Less than a year ago you bought Canon T6 (their most entry-level model, using very old tech) with kit lens (okay optically, but slower/noisier micro motor AF)... You already had some lenses left over from the previous camera (Canon EF-S 55-200mm, Tamron 100-300mm), have since added other lenses (Canon 50mm f/1.4 or f/1.2, it's hard to say from your post. Tamron 150-600mm G2).

But you were rather dissatisfied with that 18MP T6 (with processor and AF system from around 2004/2005) and the old/third party lenses you're using on it.

As of June you appeared to be contemplating a Nikon D850 and a trio of lenses: Nikkor 14-24mm, Tamron 24-70/2.8 and Tamron 70-200/2.8.

So... for travel... you propose replacing a simple, budget, 18MP crop sensor 1 lb. camera with some basic lenses (such as 18-55 weighs 1/2 lb... 55-200mm , approx 1 lb.) probably costing <$500...

... with over $5000 worth of full frame, advanced, 46MP camera that weighs 2 lb. and a trio of f/2.8 lenses that each weigh 2 or more lb. ???

I don't know if you've bought yet, but can tell you I've traveled with a full frame camera and kit of full-frame capable lenses. My minimum kit of camera with four lenses (20mm, 24-70/2.8, 135mm, 300mm f/4 & 1.4X teleconverter) and necessary accessories (flash, extra batteries, charger, a few filters, etc.) weighs close to 24 lb. and fills a small LowePro backpack (just barely fits through the TSA screening X-ray or in an airplane overhead). That kit gets heavy lugging it through airports, so I try to use smaller, lighter kits for travel as much as possible.

I was going to suggest an alternative for your wife... that instead of buying a non-interchangeable camera, you get your wife a small DSLR or mirrorless that's able to share lenses with whatever you're using. Depending upon what lens you put on her camera, she doesn't need to change it at all and can use it the same way as a fixed-lens camera. But if she ever wants to experiment with other lenses in the future, she would be ready to do so with an already-familiar camera.

But I don't know what system you're using.. or how much you want to spend. Depending upon whether it's still the Canon or you've switched to Nikon... or to something entirely different... the whole idea is to get the same brand as you're using and be able to share lenses, batteries, chargers, flash and other accessories while traveling.

Using Canon examples....

For yourself you might consider upgrading to a MUCH better APS-C model like the 24MP 80D (which is seriously on sale refurbished at the Canon USA website right now) or the new 32MP Canon 90D that's been announced and will be available to buy in a month or two. Also get yourself BETTER crop-only lenses to use on this camera, both to improve image quality and still have reasonable weight and size for travel.

If you get one of those for yourself, you could the get one of the smaller/lighter cameras for your wife, such as the Canon Rebel SL2 or SL3 (main difference is the latter has a newer processor and enhanced video capabilities... outside N. America these are known as EOS 200 and EOS 250 models, respectively).

And alternative would be to get her a mirrorless like the Canon M50. While those use their own EF-M lenses directly (which cannot be used on the Canon DSLRs), they also can use the EF/EF-S for the DSLRs lenses via a simple adapter. Canon offers an adapter, but so do Vello and other third party manufacturers.

The M50 is slightly smaller and lighter than the SL2 or SL3... but those DSLRs are among the very smallest and lightest anyone makes, rivaling the size and weight of many mirrorless with viewfinders. Mirrorless without viewfinders can be smaller, but are limited to using the rear LCD screen for composition. Both DLSRs and mirrorless w/viewfinders can be used that way too, or with their viewfinder. Viewfinders in DSLRs are optical and don't use much battery power. Viewfinders in mirrorless are electronic, which have some advantages for low light shooting, manual focus lenses and by giving exposure previews... but draw heavily on the camera's battery, reducing shots per charge significantly so more spare batteries are needed.

Some Canon APS-C lenses for travel that I'd recommend:

EF-S 10-18mm f/4.5-5.6 IS STM (small, light, inexpensive... somewhat plasticky).
EF-S 10-22mm f/3.5-4/5 USM (more robust, but a bit larger, heavier and more expensive).
EF-S 15-85mm f/3.5-5.6 IS USM (great range in a single lens... might be a good choice for your wife's camera).
EF-S 18-135mm f/3.5-5.6 IS USM (another wide range zoom that makes a good "walk-around" lens).
EF-S 18-135mm f/3.5-5.6 IS STM (same good quality optics as above, lower price and a little slower "stepper motor" focus drive).
EF-S 55-250mm f/4-5.6 IS STM (affordable, good image quality, reasonably fast AF).
EF 70-300mm f/4-5.6 IS USM "II" (more expensive, good IQ, faster ultrasonic focus drive, full frame capable).

All those lenses are reasonably compact and moderate to light weight... good for travel.

All the lenses you already have also can be used on the above Canon cameras.

Third party Tamron lenses may or may not work with newer camera models. It's a bit of a crap shoot with third party lenses. Sometimes there are compatibility issues using an old lens on a newer camera. If you stick with Canon's EF and EF-S lenses, there are no compatibility issues regardless of the age of the lens and DSLR camera... aside from EF-S lenses not being usable on full frame cameras. Personally I use a couple of Tamron's macro lenses and they've been good on a variety of cameras (though I gotta say one has stopped focusing correctly and is going to need work... about 2 months after it's 6 year warranty expired!) Tamron has had relatively few "issues" of this type.... but who knows what may happen with future cameras. Sigma has had more old lens/new camera compatibility problems... though, to be fair, they've also produced greater variety of lenses than any of the other third party manufacturers. I'm not aware of any issues with Tokina lenses. All this applies to these third party lenses on Canon cameras. I don't know about them on other manufacturers' cameras.

All this is just a thought. The cameras mentioned above for your wife have a lot of the same type of "scene modes" and what not that she likes to use. Those can be applied "in camera" if shooting JPEGs... or can be applied to RAW files using Canon's Digital Photo Pro software during post-processing (the advantage being that you can change your mind and try different styles with the image, if you wish). A DSLR or perhaps a mirrorless camera would give her "room to grow" if and when she decides to do so, but also can be used as a "point n shoot" camera for as long as she likes.

Both of you using the same system would go a long way toward simplifying things and lightening your load while traveling. If you've already bought into a system other than Canon, you can probably assemble something similar, where you could share. I'd be a little bit concerned with Nikon because there are some indications they're going to discontinue a number of their camera models in the future, narrowing choice of DSLRs to only a few of the higher end models and concentrating on making mirrorless cameras (which use a different mount, though many of their F-mount DSLR/SLR lenses can be adapted). Presently Nikon only makes full frame mirrorless (in addition to FX and DX DSLRs). Canon makes both full frame and APS-C mirrorless, in addition to both FF and APS-C DSLRs. (EF-M and RF lenses for the mirrorless are not interchangeable though.) Sony also makes both FF and APS-C mirrorless, as well as lenses for both. I'm not familiar with their A-mount and E-mount lenses, and their interchangeability. Fujifilm only makes medium format and APS-C mirrorless. Olympus and Panasonic currently only make Micro Four/Thirds format mirrorless... sensors a bit smaller than APS-C... though Panasonic is introducing a FF mirrorless. Pentax (Ricoh) is currently only making DSLRs in FF and APS-C format (as well as medium format digital).

Personally, for travel (and some other things) I'd like to have an APS-C mirrorless with a small kit of lenses. I looked hard at... and am impressed with... the Fuji system. But after careful consideration I've pretty much decided on getting one of the Canon M-series cameras and a few Rokinon/Samyang manual focus lenses. I can put together an entire system of Canon camera and lenses for less than the cost of the Fuji camera body alone.... By the time I got the lenses for the Fuji, I'd have about doubled the cost.

If you still want to get a non-interchangeable lens, "point n shoot" for your wife, you might also want to look at the Canon Powershot G_X series. There are four or five models of those. They use 1" (CX) and APS-C size sensors that make for very near DSLR quality images. All the Canon "G-series" also have high quality, modest range zooms (approx. equivalent to 24-100mm or 24-135mm on "full frame/film"... wide angle to short/moderate telephoto). Beware of that type of camera with a huge zoom range.... to accomplish that range they use tiny sensors that limit image quality and how high ISO can be used.

But I still think it's worth considering a DSLR for your wife, since it can be used in much the same way. She doesn't need to change the lens unless she wants to!

Hope this helps... and gives you some food for thought regarding some alternatives.

My 128GB San Disk Pro was finally about full of mostly RAW images, so I made sure that I had transferred everything I wanted and reformatted the card in my CANON 80D, using the standard formatting option. I then shot several hundred images in the 80D. It seemed to me that the write speed to the card had degraded somewhat. It occurred to me that maybe I should have done a Low Level format, which deletes all information and data on the card, vs just the normal formatting which simply resets the file system.
So to test this hypothesis, I formatted the card again in the 80D, selected high shutter rate and set the camera to Manual. Holding the shutter down, I got 25 exposures before the buffer filled and the write speed slowed to a crawl. Then, I reformatted the card using the low level formatting option, everything else being the same, and held the shutter down until writing slowed to a crawl. This time I got 32 exposures before the buffer filled and the write speed slowed to a crawl.
So, this little experiment tells me that if you want to get the most out of a top tier high write speed SD card, you should do low level formatting rather than the quick and dirty standard in-camera formatting.
Has anyone else seen this effect?

Looking to buy something to upgrade for my wife. She's been using various iterations of the Olympus "Tough" line point and shoot. Used them while we were cruising on a sailboat in Central America a few years ago, and she has a ton of really nicely composed shots, albeit that the IQ is limited due the camera. She likes to use the "in camera" scenes and special effects. But she's also seen some of the stuff I get with a DSLR, and is about ready to get out of the "auto" mode, and actually learn the subtleties of Aperture, ISO and shutter speed.

I've been looking at some of the "super zooms" like the Panasonic FZ1000, Sony RX10 & Nikon Coolpix P900 lines, but at the cost and size, I figure it's best she just learns to hold the DSLR with an appropriate lens. But there's lot of time she won't want to haul that around, so I started looking at some of the fixed lens options.

The two that I've narrowed it down to in that category are the Fujifilm X100F and Panasonic LX100 II.

Kind of leaning toward the LX100-II, mostly because of the (albeit short) zoom. Any thoughts suggestions or constructive criticism would be greatly appreciated.

Below are a couple of samples of the kind of stuff she (likes &) does. These were done with the in camera modes. Not PP on a computer.