Not sure how long it's been since you've tried Linux, those all actually work perfectly out of the box. Even the online works on Bf4 and Gta5. If you have Steam, you just download and run them like you would on Windows. Though I'd say go to the properties and change to "proton experimental" for a bit of a better experience imo, but not needed.
If you want to check without downloading and testing yourself, you can check this site for how well it runs, vs if it needs tweaks or flat out doesn't work. https://www.protondb.com/
Because it's not a choice of FOSS or not, it's a in choice of quality of the app. Apps like Jerboa or Thunder are very far behind Sync and Boost. But if you enjoy those, then more power to you, and definitely no reason to switch.