ngl, sometimes it is. it depends on the game. usually the problem is anti-cheat, but Valve has been working on improving that with many games working out of the box today. i’d say if you’re playing single player games, once you get Proton installed it’s virtually the same experience.

check out https://www.protondb.com/

if your games are gold or above on there, i’d go ahead and pull the trigger.