It just means "noone" uses the wayland APIs directly, but instead they leave the wayland complexity to GTK,Qt or FLTK, and they call their app a Qt app, not a Wayland app.
Was X11 any different in practice? Apart from ancient legacy stuff like XTerm. It would be like writing a Mac application in Quartz directly.
Then in that case, the point is moot, as a similar version of "no one" uses the X11 APIs directly anymore, either.