Early on I consulted ProtonDB to see if my games would run, but honestly now I don't even look at it any more. While YMMV depending on the games you play, I haven't encountered really any major bugs and zero crashes. The most I found was some strange shadow texture rendering artifacting in Baldur's Gate 3, but it was contained to a particular part of a particular map.
A decade ago it was kind of rough, but now? I am never going back to Windows for gaming. Playing games on Linux is light-years better than what it used to be. If you're curious but haven't tried it because you had bad experiences in the past, I'd encourage anyone to give it another go.