As a worldwide award winning pro with four decades in the business, I have used exposure compensation dials on my cameras for many years in countless photo situations around the world. And as a longtime Professor of Photography at a state university, I have to teach about this to my photography students.
While viewing the scene and the otherwise "correct" exposure in my EVF, I may quickly determine by experience or with viewing the histogram without taking my eye off the EVF (cant do that in a DSLR) that my primary subject may need more or less exposure to retain detail in that subject's key tonal range .
Like moving from an all high-key subject in bright light ,like a winter scene in snow, then into a low-key subject in
shadow. No metered "correct" exposure can quickly handle the quick move I need, so a quick move of the exposure compensation dial can give the correct exposure I need, while retaining any key choice of f-stop or shutter speed chosen in either aperture priority or shutter priority.
I may be hard to visualize what I am talking about, but pros and hobbyists alike make great use of the exposure compensation dials on their cameras and I wouldn't want any camera without one.
With a DSLR and an OVF it would be more critical to be sure you returned it to zero when changing your scene. With a mirrorless camera you can easily see your exposure settings effect in the EVF. Both DSLRs and mirrorless will display the + or - of your exposure compensation settings.
https://digital-photography-school.com/how-to-use-exposure-compensation-to-take-control-of-your-exposure/https://www.dpmag.com/how-to/tip-of-the-week/exposure-compensation-how-it-works-and-when-to-use-it/Some online comments from experts on using the exposure compensation:
" It's likely that you'll need to use exposure compensation when you're shooting something that is predominantly black or white. Shoot a white scene (such as a snow-covered landscape) and the camera will tend to under-expose the whole scene."
"The exposure compensation dial (or adjustable menu setting) allows you to influence the way the camera determines a correct exposure. It's like your direct line to tell your camera, “Hey, whatever you think the correct exposure should be, I'd prefer it if you over- or under-exposed from there."
Cheers and best to you.