I'm a Linux user as well (arch btw) and I just look at protondb and https://areweanticheatyet.com/ as a reference. If something comes up as less than stellar, I'll just skip purchasing it.

Longest I had to tinker with were Project Zomboid (due to ancient gfx before I bought a new one) and Jedi Fallen Order (just to fine tune for performance/fidelity, took about 15 minutes).

I understand if you regularly go for games that require a lot of tinkering you might need more time though, but the Steam return is 2hrs of played time, not 2hrs of owning the game.