Using Windows primarily for gaming, I eventually got tired of some of the issues I had with it (ads appearing in the start menu). I gave Linux a try and it was so so for a while. I kept going back and forth but it's been 2 years now and I haven't had Windows installed and can play 90% of my games without issue. I wouldn't recommend it for everyone. But for those that primarily use their computer for gaming and non-windows specific applications (like web browsing or other various things), Linux is offering some competition for desktop people.
Some games use kernel-level anticheat. Unfortunately, because there is a kernel driver involved, it must be specifically ported to Linux, and some developers simply don't want to bother.
It's mostly going to be games that use anti-cheat software (though some work on Linux.)
So if you're someone who likes to bounce around to the hot new competitive online multiplayer title then Linux probably wont serve your needs right now. If you can't think of a single esports title you want to play, once you install Steam and Lutris you'll probably find nearly everything you want to play works.
I run No Man's Sky on Nobara Linux, installed it on my old laptop that barely gets by on Windows. Really breathed new life into it and I haven't had troubles.
Just installed it on steam after checking the box for proton compatibility. You might need to run a task kill command if it gets stuck in a DirectX install loop on launch but other than that it's been smooth sailing for me.
I can say offhand that No Man's Sky put a lot of extra time and effort into their Steam Deck support so that definitely works. Otherwise your best bet is to check either the Steam listing for a game (check the Deck Verified rating. Anything rated "playable" or "verified" should work pretty seemlesly on any Linux gamingPC) or https://www.protondb.com/ (a user run listing of the compatibility of different games. A good resource and often has some troubleshooting advice. Unfortunately it can often have outdated or just inaccurate information as it's all based on user reports. Still usually a pretty good indication of compatibility.) There's no indication on either regarding Starfield compatibility. Given that it's probably too resource intensive for the Deck it may not get as much special attention from Valve as something like Elden Ring (which ran better on Linux than any other platform after it was out for a few days and Valve had added a patch to Proton to fix an issue that the developers took longer to patch in the game itself.) Chances are pretty good it'll work though (assuming your hardware can run it.) The Steam page for Baldur's Gate 3 says it's Steam Deck Verified so it'll just work so long as you launch it through Steam. Here's the protondb page for reference https://www.protondb.com/app/1086940 . Crusader Kings III, Rimworld and Stellaris apparently all have native Linux ports so, while you may find reasons to prefer running the Windows versions with Proton, you don't actually need to check for any special compatibility. They just are Linux games.
It really sounds like I've been sleeping on recent Linux compatibility then. I remember back in the days of Wine it seemed more a PITA than was worth it.
Yeah Steam/Proton and other tools like Lutris make it so you don't really even have to touch Wine for most stuff, it's all taken care of for you. Gaming on Linux has come a long, long way in the last few years.
BG 3 runs on the Steam deck, mostly without issues (except for those that aren't Linux related, like text being hard to read due to the small display and lower frame rate due to the portable hardware).
Most of the Paradox games support Linux natively. I play Europa Universalis 4, Stellaris, Crusader Kings 2 (haven't bought 3 yet but it has native support), Hearts of Iron 4. Victoria 2 doesn't have native support and I didn't get Vic 3 but it is supported. Rimworld is native, so is Factorio.
Have a look at what you want to play on protondb.com and figure out if gaming on Linux works for you. Baldur's Gate 3 has a gold rating (gold being one level lower than platinum - the best rating for non-native games) which for all practical purposes should work.
Mostly games with anticheat or very new games. Everything else pretty much just works especially older games. I needed to visit pcgamingwiki all the time to get older games to work on windows but for linux I mostly just visit protondb and find out I don't need to do anything or need to just put in launch command. System shock 1 was the only game I had to actually go through a process to get it running with audio.
The biggest one I miss, and it works, but the anti-cheat keeps me from my favorite servers is anything from the Red Orchestra series. I really enjoy their newer game Rising Storm 2 but the vast majority of the servers are protected with an anti-cheat that keeps me from joining. I've found a couple servers that don't use the anti-cheat and I can play on those, but they're not quite the same as some of the servers I have as favorites that are playable on Windows. Otherwise, most things generally work good, biggest problem is with launchers, and even those can be bypassed or fixed, but I've gotten to the point in my life where I just want things to work without having to remember what config files I've changed or futz with that may break in the future. The other games that I've had that don't work may as well now, but honestly I've forgotten what they were. One that I don't play, that I know a lot of people do is Destiny and I saw that they'll ban you if you try on Linux. But I've only heard that as I haven't played that on PC.
beyond anti-cheat and "just came out" there's one more category that often doesn't work: not-new, obscure games.
Anything that isn't pretty new and/or pretty popular may need to you run through some hoops to get running right.
If you like jumping from game to game a lot, I wouldn't recommend Linux, but if you stick to a few and play them for a long time (and you don't mind the extra work it is to learn a new OS) I think it would be worth making the switch.
EAC (Easy AntiCheat) works just fine on Linux as long as the developer enables it. There are very few anti-cheats that don't work anymore. The ones that aren't as big like Vanguard, which is Valorant's anti-cheat, don't work, but Battleye, EAC, and VAC works just fine.
Check out protondb.com for a pretty great resource in what games work/kind of work/don't work on linux (with proton specifically, which is how most people play Windows games on Linux). It's far more accurate than even Steam's own "verification" system for Steam Deck.
It's pretty amazing what they've done with it over the past few years.
Yea I've always found that complaint odd. I just assumed everyone who makes it also has the activate windows watermark, and thus can't access the option.