Been using it for a couple years, my main ones currently are:
- VR. SteamVR is a broken mess, Monado is pretty much functional, but I haven't switched yet. Mesa or the kernel sometimes forget about VR and break it in an update.
- QT5 to QT6 transition for my favorite Matrix client, Nheko. Scrolling is a pain, and the clipboard randomly stops working.
- Wayland freedom and featureset is nowhere close to X11. I can't choose a window manager without locking myself in to a specific featureset on my display server. Stuff like global hotkeys isn't supported in most applications. I'm still on the godawful GNOME desktop portals, which is most annoying for file picking. I have no HDR support because my window manager isn't from KDE or GNOME.
- GTK4 apps looking like shit (there are patches luckily), I try to avoid them just because of
libadwaitaand GNOME's awful design.
On the note of Wayland, I have switched, and for good reason. Besides unimplemented features, things "just work" a lot better than X11. Still wish I could have effectively bspwm window management with kwin featureset though. (Plugins for tiling are not the same experience)