Crop, no crop...
First off it takes place while composing IN CAMERA. You always need to plan for the final products(s). The most restrictive is the key*. When dealing with the initial SOOC capture you must vision/plan the final product, SMALLER than the frame offered so that the residual margin can be used if there is a need for straightening. On a tripod, if you are experienced, it will rarely happen. Handheld on the other hand it is a must to plan for errors - so that you can correct it/them if you make one. Better safe than sorry.
To claim that you edit better if you crop before because of your final format is counter productive. Just consider the variety of formats/ratios that can be pulled from a single capture you must give this up rather quickly unless you want to waste your time 'PPeing' every crop. Good luck with that. Still, to each their own, I guess.
Basically, in my opinion, for whatever reason, training/habit/whatever each photographer creates his/her own workflow that fit the person's style. Bad habits are hard to break and anything can be used justify them.
I pay attention in SOOC first.
I process whole (not only global - local edits are there to stay too).
I crop at a set requested ratio STILL with a proportional margin to allow for framing, Yes, those pesky little things can also cut toes and chop-off hairs.
Note that I use crop to rectify the vertical lines if needed and then apply a vignette or not if the capture demands it.
Since a crop can be redone in seconds I save the un-cropped version first (and stop saving the file). Crop/straighten/last touches, print/export to printer outfit. If or when I need a newer crop ration I just press F12 to return to the saved version and repeat the steps as many times as necessary.
Sounds more complex than it really is but it saves time and is, in my opinion much more efficient than having multiple copies of the same thing with a different ratio.
By the way... This is where high pixel cameras excel...
Oh, since I am at it... Shoot raw too!!!
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* 1x1 is the real b*** here. If you need this ratio among others you will have some serious crops in all the other ratios so beware and even just take two shots if you know this is going to be a liability.