I run a heavily modded Skyrim on my deck and it plays fine offline, but the launcher won’t work offline for some reason. So, I can play it as much as I want, so long as I don’t completely exit the game. Its probably a solvable problem, but I’m rarely without a connection or at least the ability to use my phone as a hotspot just to run the launcher.
At this point I’m mainly still on Windows because it is the easiest thing to do - I know how to use it and it is already installed on all my PCs. At least 3 of my PCs are eligible to upgrade to Win11 (2 are not), but I have no plans to ever upgrade. So, when security updates stop, that will be my motivation to give Linux another try.
In games that don’t have good auto-save (like Skyrim), I’ll map one of the back buttons to quick save.