oh they never agreed where to put stuff on Windows either.
the "My Games" folder under documents? hah! a flight of fancy that never caught on.
just a folder with the game name under Documents? messy but at least the average user can find it. but wait, there's more!
%APPDATA%? Well most gaming probably doesn't happen on a roaming profile so it might be okay but has the same flaws as out next contestant
%LOCALAPPDATA%? Okay, but which obscurely named folder is it buried inside of there. Is it the game name? Is it the company name with another game name folder inside it? Is it the internal project name that is for some reason impossible to change in all major toolchains?
The game program folder itself? Yep games still do this. Navigate through your steam client to find out where it was hidden.
%LOCALAPPDATA%\VirtualStore? Haven't seen this one in a while but this is what happens when an app thinks it's still 2000 and there's world-write on directories like "Program Files" and Windows goes "oh that's cute, let me just let you think that works".
And when they're feeling really spicy, they don't use just one option!
Cheat code for this for Steam games that support Steam Cloud saves is to just look at the cloud configuration with a tool like SteamDB. Shows you the paths, patterns matched, per-OS and even with handy substitutions. Still not ideal but I've made peace with the fact that video games will never settle on a good standard for this.
Examples: Celeste, RimWorld
You can't do this for games that don't support Steam Cloud but quite frankly the developer is doing you a huge disservice in general if they don't support that and obviously this only applies to Steam games, but I think it's still good to know.
And if you're feeling really confident and want to backup everything all at once at the cost of some waste, copying your entire steam compatdata folder with symlinks will contain all save files for games running through proton, but this is far from ideal.
