Not everyone has the same repertoire of games and not every game will run natively on linux. Depending on your flavour, messing with a compatibility layer can be fussy for some people and depending on your choice of games, your ratio of native/near-native:compromise:does not work will vary. It can’t be “it works for me so it should work for thee”.
Of course – but that works the other way as well. It doesn’t mean Linux gaming is lacking somehow if your library happens to be filled with the few remaining problem cases.
My point is simply that, by and large, it’s ready and seamless, and things like Protondb support this.