The silence is eloquent. I hear "status quo is preferable" loud and clear. Works for me 
Perhaps it's worth detailing where we are now with x11 and wayland:
x86 (TinyCore)
Xvesa, Xfbdev and xorg-server are all available
mesa is not compiled for wayland in the interests of keeping things small
fltk-1.3 does not support wayland
x86_64 (TinyCorePure64)
Xfbdev and xorg-server are available
mesa is compiled for x11 and wayland
fltk-1.4 supports wayland so the tinycore applets are available in a wayland compositor
armhf (piCore)
xorg-server is available
mesa is compiled for x11 and wayland
fltk-1.4 supports wayland so the tinycore applets are available in a wayland compositor
aarch64 (piCore64)
xorg-server is available
mesa is compiled for x11 and wayland
fltk-1.4 supports wayland so the tinycore applets are available in a wayland compositor
x11 is becoming increasingly unsupported, particularly for x86 (xorg-server will not start with my intel hd4400 graphics using the modesetting driver, but will start with the obsolete xf86-video-intel driver)
wayland is becoming increasingly supported, wayland-only test versions of x86_64 and aarch64 work well (firefox works noticeably better on an RPi3 with wayland as compared to x11). All gtk3 and gtk4 apps work with wayland.
XLibre might make sense for x86, particularly if it updates Xvesa and Xfbdev (I don't know if this is planned), but I'm not sure if it makes sense for x86_64, armhf or aarch64.
The decision to be taken is perhaps not deciding between x11 and XLibre, but rather deciding between x11/XLibre and wayland.