You can certainly play plenty of games on it. The user experience is materially worse, though. While these are complaints, I appreciate that Valve is making an effort to support Linux.
Just tonight I was mucking around with Remote Play from my Linux desktop to an Android phone.
* Lock screen got in the way. Attempts to unlock remotely froze the client.
* Game launched in windowed mode, ended up shifted and cropped. At least it launched! Putting it into borderless mode got it to fill the client screen properly, but rendered at a higher than optimal resolution.
* Sound didn't work on the client, only the host. Checking "play sound on host" fixed it?!
At least I eventually got it all to work.
SteamVR in Linux sort of works too.
* Async reprojection doesn't work and leads to horrible artifacts. The option to disable it globally is missing, and you have to go deep into the per-app settings.
* Sound has a 50% chance of being borked. Unplugging the headset sometimes fixes it.
* If you have an AMD GPU, its automatic power profile causes latency spikes several times per second. You either need to write to sysfs entries, or install third party daemons, and you need to add a kernel option in grub. Fun!
* Bluetooth power management for base stations doesn't exist, except for some third party scripts.
* If I have multiple monitors enabled, the headset fails to go into direct mode.
* The virtual controllers shown in the base environment are rendered as if the z-buffer is inverted, or maybe the normals are backwards. I'm pretty sure it's a bug in AMD's openGL implementation.
Google Earth works great. Attempts to launch Star Wars: Squadrons so far have failed.
Quite a few, actually. The Steam Deck made swathes of Steam games previously incompatible work with Linux. EasyAntiCheat notably works on any game that bothered to update its libraries, for example.
There are still plenty of titles that don't work, though. Personally, I don't care enough about them to find out if there are any fixes or workarounds, I generally just add the game to my "broken" list and play something else until the game developers fix their problems.
If you stick to Steam, though, there's a good chance your favourite games library will just work out of the box. Epic is actively anti-Linux so don't expect games on the Epic store to work and god forbid you try to use the crapware EA and Ubisoft force you to install. N=1, but I've been doing all of my gaming on Linux and almost everything on Steam just works for me. I've only had trouble running Halo but I found out that that was because of some kind of DRM sabotage by Microsoft, so I just ignored the game and moved on.
