The sad part is that the DE boys keep thinking that more eyecandy and bling will bring in the users and thus the third party software (apps? bah!) devs.
But as JWZ put it, Gnome (and most of the XDG related stuff) is beset with CADT. They fail to see that the one thing that has kept Windows where it is right now is that some company can still run their bespoke business code that was written back in the Windows 3.11 days.
Damn it, they can't even manage to do minor updates to glib and related without introducing subtle breakages.
And no, Flatpak and related is not a fix. That will just bring the specter of DLL hell to Linux.