Once Wayland components developers started trying to implement something practical, they discover, one by one, that they need those "unnecessary" X features after all.
Wayland has shot itself in the foot by being marketed as a replacement for X. But it's not really meant to be the entire car: this is just a new engine (that exploits low-level features of the Linux kernel). You could retrofit this engine into the old car (X Windows) or you can build entirely new cars with it. You won't see it on the highway tomorrow, but ~10-20 years from now it might be powering everything and putting a lot of exciting new cars on the road.