I have an opposite view. X11 has two key aspects separated to two independent entities: mechanism (in Xserver) and policy (in window manager). This has and advantage as neutral mechanism can be shared by everybody (Xorg), while everyone has different opinion about policies (many WMs).
Wayland assumes integration of compositor (mechanism) and WM (policy) to one entity.
All I can say is that nearly every single one of the former core Xorg developers has said precisely the opposite (sometimes in literal terms [0] [1]), and has switched to developing Wayland.
[0] https://www.youtube.com/watch?v=GWQh_DmDLKQ&t=27m44s
[1] https://community.kde.org/KWin/Wayland
> In Plasma we need Wayland support as we are hitting the limitations of X all the time. Wayland will simplify our architecture and allow us to composite the screen in the way we consider as most useful.
By contrast the common complaint about Wayland is that it doesn't have the vast variety of unrelated features rammed into it like X does.
Part of the problem here then is that there's A) no big pushes for 'does one thing & does it well' for all the other X features (like clipboard or global keyboard shortcuts), and B) fragmented implementations of the wayland protocol. There really should have been a much better, and more singular, reference implementation that Gnome, KDE, etc... all just embedded instead. Which means the "does it well" part is taking a really long time, as developer communities are split up.