Steam Deck and by extension Proton being heavily funded by Valve mean that Linux is a seriously viable gaming setup now. I can play pretty much every game I want to play on Arch Linux now. Even games that don’t support it (NB: you need to enable use of Proton in the Steam client).

You can check here for games that will run on Linux to make sure your ‘must haves’ are supported: https://www.protondb.com

Personally I’ve been playing Apmplitudes games (even pirated ones [Humankind, Endless Space, Endless Legends]), Cities Skylines, HOI4, Stellaris, Dead by Daylight, etc.

I’ve actually found a few games (Paradox esp.) run better on Linux (using Proton) than they do on Windows.