Depending on the game, there's still that classic linux hassle (aka series of hacks you can impress your friends with) that are needed to get some games working, but the number of games supported and working without the hassle is honestly surprisingly good imo. The typical ones that you can expect to cause a headache are the always on live service games with heavy handed DRM.
Depending on the game and its DRM, the SteamOS has been great. A couple of symlinks are required to run some stuff but proton pretty much bridges the divide.
Depending on the game, there's still that classic linux hassle (aka series of hacks you can impress your friends with) that are needed to get some games working, but the number of games supported and working without the hassle is honestly surprisingly good imo. The typical ones that you can expect to cause a headache are the always on live service games with heavy handed DRM.