I've been running games that advertise they run in linux for a few years, but only within the last 6 months or so started trying out made-for-Windows games, and it's really incredible just how good the Proton compatibility layer is now. All of the games I've tried are at least playable - most run perfectly, a few are a bit slow, and some you have to tweak settings but there's a big database of how to get different games to work at appdb.winehq.org. Not one of the games in my library don't run on linux at all, other than a couple with kernel anti-cheats that I don't play any more anyway.

I was dual-booting but a couple months ago I deleted my Windows partition and now I just run linux full time. If a game only runs on Windows, I just won't buy it.