The system also does pretty well in the long tail. There's even a set of older (and some newer) games that run better than they do on modern versions of Windows - not a huge number, but not nothing and probably growing over time.
At this point, the largest problem left to solve is perhaps achieving pervasive support for anti-cheat middleware by multiplayer games, which requires vendor participation. A few have started collaborating, but there is more to do on this front.
(Disclaimer: I work on KDE and worked a small bit on the Deck at some point.)
Playable is good enough. It may have small text, keyboard only references in text, or other minor annoyances but a playable game does work on deck. On desktop or laptop linux for many of them you may not notice any issues at all.
Yes, the release of the Steamdeck did wonders for pushing AAA gaming forward on Linux.
There was just an article on the front page earlier today about 75% of the top 100 games on steam running on linux, with the remaining 25% mostly being due to anti-cheat software that isn't updated to support linux yet.
Protondb.com has a database to search for compatibility and if adjustments to command lines or a specific version of Proton are needed for getting games running.
