I have been using X11 since 1996, and I never felt that it was very good. Sure, at the start it was better the then state-of-the-art desktop (Windows 95), mostly thanks to Linux, but that advantage went away in 2001 when OS/X was released. And even Windows went past it at some point, perhaps around Windows 7 or 8.
Wayland took a long time to get there, but it definitely is there today.
It’s like a good C++ that is actually able to replace it. There are lots of places where a good C++ is useful. Like everything that needs low latency and low resource usage.
But it’s not an easy language, so (I’m guessing) people who see everyone loving it but are unable to learn it start to suffer some sort of cognitive dissonance. If it’s too difficult for me to learn, that must be its fault, not mine.