Wayland, itself, is just a protocol. The display servers are just the display servers. But then you have Gtk and Gnome, Qt and KDE, software like Firefox and Chrome, etc. All of those have to updated as well, and while Wayland the protocol, the display servers, and a lot of the suite of infrastructure around it is in pretty good shape, the toolkits and clients and so forth all still need a lot of work.
And you only need to look at the Python 3 transition to see how hard it is to shift a whole ecosystem.
So I'm willing to cut the Wayland guys some slack. But it does mean there's still a ways to go, yet, before things are ready for prime time.