All fair points, but honestly? I fully expect comparability layers to be at least somewhat flawed and I adjust the way I do things accordingly. Game doesn't work 100%? Whatever, I have other games to play.
At the end of the day, I don't want to reboot just to play a game. I personally don't see the need to be a comparability purist here.
If on the other hand we are playing the quality card, or what everyone else is actually paying for, then down Proton it goes.
Isn't ironic that while most Android games are NDK based, so basically ISO C, ISO C++, OpenGL, OpenSL, Vulkan, they don't get ported to GNU/Linux?
Or Stadia ones for that matter (regardless of its possible future).