For me personally on an AMD GPU, Wayland seems feature-complete. In terms of bugs though Wayland can be a pain. My primary monitor always seems to lock up either entirely or in parts. Like I can use the taskbar but a game becomes unresponsive, or vise versa. Literally as I typed this, my taskbar locked up and I can’t select anything so I will have to reboot lol.
Another annoying thing about KDE under both X and Wayland (though it happens in Wayland far more) is when the taskbar and title bar icons default to the display server logo. I hate that. Probably on the app developers though.
GNOME under Wayland is a different story, I ran that for a year and outside of some external monitor funkiness everything just seemed bug free. Might switch back once GNOME gets VRR support, we’ll see how Plasma 6 is.
With extensions GNOME can become very Windows-like as well. This is how Nobara is set up by default, for example.