Has it really been that long? Apparently so. Valve originally announced their rebranding of Steam Play with Proton back on August 21st, 2018. Seems like a good time for a quick reflection being halfway to a decade old now with the tech that gave rise to the Steam Deck.
I was able to ditch Windows completely thanks to them, haven’t had to dual boot for years. I remember back when I first tried linux there were only a handful of games that would run without hours of tinkering. Now compatibility is an afterthought; I just assume Steam games will work and I haven’t had any issues yet.
Problem for me is def going to be modding games, have they fixed alt tabbing between games and desktop yet at least? It used to “crash” the game for me if I tabbed out even for a second.
I’ve never had this issue but it might be specific to the game you’re trying, using gamescope might help.
You can try to use gamescope for that. Really useful for games that crash alt-tabbing
The only (large enough) area which is currently lacking is multiplayer games, especially those with anticheats. Unfortunately, there’s nothing users can do about that other than wait for game developers to enable wine support, which, despite EAC and Battleye significantly simplifying the process, many still haven’t done.