That is not what the protocol is like at all. Wayland can't do certain things not because they are difficult to do, but because Wayland was initially pathologically minimalist (I say that as somebody who generally likes minimalism) and the approval process for extensions has only improved slowly over time. It turns out that there's much more than blitting rectangles to a (single) screen and routing input events to a desktop environment.

If all the expected stuff was there, Sway (chosen because it's not tied to a desktop environmen) could be your X server equivalent.