There's just no reason to do this work. Even if you ignore the fork's controversial maintainer, and just favor the fact that it's maintained at all (which is what the proposal's author is suggesting) just... Why?
X11 is basically over at this point, why throw a last minute wrench into the existing, working Xorg infrastructure?
When we dropped XFree86 back in the day there were license issues, packaging issues and a real alternative didn't exist - all justifying the effort to switch. None of these are a problem today.
