As a third party, my understanding is that both the implementation and the protocol are really hard, if not next to impossible to iterate on. Modern hardware doesn’t work like how it did when X did, and X assumes a lot of things that made sense in the 90s that don’t now. Despite that, we cram a square peg into the round hole and it mostly works - and as the peg becomes a worse shape we just cram it harder. At this point no one wants to keep working on X.
And I know your point is that it works and we don’t need too, but we do need too. New hardware needs to support X - at least the asahi guys found bugs in the X implementation that only exists on their hardware and no one who wants to fix them. Wayland and X are vastly different, because X doesn’t make sense in the modern day. It breaks things, and a lot of old assumptions aren’t true. That sucks, especially for app devs that rely on those assumptions. But keeping around X isn’t the solution - iterating on Wayland is. Adding protocols to different parts of the stack with proper permission models, moving different pieces of X to different parts of the stack, etc. are a long term viable strategy. Even if it is painful.