They probably meant "everything that they use it for". Like, in my case everything on Linux works for me, but I don't play multiplayer games or use Photoshop. I have a single old monitor that can't do HDR. I don't watch Netflix. To be fair and pedantic, not everything anyone could possibly ever want to do works on Windows 11, either.
Of course I haven't tested everything. But I've tested over 25 games and havent add issues. I do some serious audio editing (Reaper + tons of VST), video editing (Davinci Studio) and even tried some game engine stuff on linux (Unreal , Godot). Pretty much everything worked out of the box on Nobara. It's optmize for games and AV. Honestly, even a year ago, I had no idea Linux was so good. I use (and teach) macOS for work, and was using Windows for gaming, but now I can do 90% of my things on Linux.