Wayland destroys backward compatibility, destroys everything we knew about the graphics subsystem, offers to work with graphics in a different totally new way which results in a ton of concessions.
A lot of Linux users do not use either Gnome or KDE and outside these two DEs, Wayland is a total PITA to use. I'd say it's just broken.
Wayland is backwards compatible, it literally has XWayland which is a completely transparent way of running any X application (with the caveat that these X apps can see each other, so not all of the positives of wayland apply).
Wtf, graphics subsystem? Wayland implementations use the standard kernel DRM interface - if anything xserver was always a red herring here with proprietary blobs for nvidia being part of the program itself, instead of being a separate driver.