This is not out of the realm of the possibility. But by the time a new protocol is needed, applications will hopefully be much cleaner if they migrated to Wayla

This is not out of the realm of the possibility. But by the time a new protocol is needed, applications will hopefully be much cleaner if they migrated to Wayland in between (less X-specific hacks, better compartmentalization of features). It would probably be easier to implement interface for backwards compatibility with Wayland than try to emulate the monolithic X (well, Xwayland is X running under Wayland because there's no other choice, so that's a possibility as well).