Pretty good. I haven't had to play around with proton launch options in a good while, Valve and the Heroic team have done a good job making it all plug and play. I don't generally play the latest releases and am not really interested in multiplayer though, so YMMV.

The user experience, and required troubleshooting, is still obnoxious. Even on the steam deck it's obnoxious. It's just not reliable, much as people hype it up. You'll have to do a lot of troubleshooting at unexpected times when you really don't want to be troubleshooting or might be pressed for time.

If you have an nvidia graphics card you can expect trouble with drivers, too.

If you have Windows 10 pro (or I think there's a workaround to enable it if you just have the Home version), you can go into the group policy editor and disable those annoying pop-ups. You can even disable auto-updates, if you want to, or control how they work. And you can disable most of their telemetry. Windows 10 has a lot of flexibility if you know where to look/figure it out. They make it annoying to deal with, yes, but it has never been has horrible as Linux is for me whenever I've tried it, and it's actually reliable.

I use Linux Mint at home and Windows 10 and 11 at work. The UI is basically interchangeable, I use both in the same manner.

I've had zero reliability issues and Mint was easier to install than Windows when I did it 4 years ago (not had to reinstall it yet, just kept on updating).

Games wise, I just play stuff through steam or classic emulators and it works well enough that typing this is the most I've thought about how it works for a long time.

I'm guessing the people who complain are running some gnarly full-custom linux on new hardware and trying to get the latest games to run ... that was once me, I now use a PlayStation for newer games because PC gaming was just a bottomless money and time pit.