If by better you mean legacy code which is hard to refactor and cannot be adapted to a modern environment without breaking everything. Might as well start fresh, that’s what mac os did and for good reason. Go ask a pen tester whats easier to break into. In the modern day of surveillance, security for the common user becomes important. If it was that easy it would have been done a long time ago. Apple has a vested interest in it, Red Hat does, Suse does, Canonical does. Why hasn’t it been done? Just like systemd there was a need for it. Is it perfect? no. Does it have to be? no. x11 was written with main frames in mind. Does any one own a mainframe anymore? didn’t think so. It’s a different time, different solution.

KDE, but wish that stock KDE had better integration with wayland. X11 is bad for security. Would be nice to have the DE be written in rust, because would have a smaller code base and harder to privilege escalate on. In reality though, easy to use and doesn’t reinvent the wheel.