Most of X.Org is horrible and the entire system is unmaintainable. It is hard to even get maintenance releases for it released, as the article alludes to.
Development hasn't stalled because people think X is good. Development has stalled because the fundamental design is so misaligned from the modern graphics stack that improvements are not worth attempting.
The thing is, X.Org server is not X11 the protocol.
X11 could be easily implemented on new driver framework supporting new graphic stack. Instead we got a piece of sh*t that is fitting for a custom embedded device or some closed environment, but not an X11 replacement.
Nobody in particular wants to use the X11 protocol. It is complicated and supports a bunch of weird functionality that is rather niche. The trend seems to be to use OpenGL and call that done.
I haven't seen many serious complaints that Wayland doesn't support the X11 protocol since people can run an X server directly using XWayland.
As I mentioned elsewhere, XWayland isn't actually compatible if you want to support modern applications, for example ones that might expect a systray. ICCM is, iirc, broken (I haven't spent time checking after finding out some apps critical to me didn't work at all).
X11 could be updated a lot. But some of the "weird functionality" is stuff that is slowly becoming available for normal people that was thrown out with the bathwater by GTK3, like ability to use more than 8bit per colour channel.
> As I mentioned elsewhere, XWayland isn't actually compatible if you want to support modern applications
Yeah, Wayland is a bad protocol. It isn't flexible enough to do what X11 does. But if it was a good protocol, and capable of implementing X11, then it would get X11 for free through XWayland.
They don't need to reimplement X11. They can use X.org or whatever for that.
My point is that XWayland, for various reasons, does not replicate X11 fully. So yeah, I can open something like Xnest/Xephyr. At that point, the utility value of Wayland drops ridiculously heavy from my point of view.
It is theoretical until you've done it. People who worked on XOrg decided to abandon it and create Wayland. X11 is not good enough for them but is good for you...
Development hasn't stalled because people think X is good. Development has stalled because the fundamental design is so misaligned from the modern graphics stack that improvements are not worth attempting.