On GNOME the documentation seems to have stagnated, then we had Anjuta, now GNOME Builder (which tries to be XCode like), a UI design tool that is being re-written from scratch, the various frameworks don't seem to compose, and then each binding does their own stuff, only adapts a couple of Gtk tutorial samples to their own language.

Naturally being GNU/Linux, everything that falls out of the UI only has POSIX or GNU/Linux specific C APIs to refer back to, yet another experience completely devoid of how things work on macOS (there is no Foundation, Accelerate, Core...).

I find this statement humorous because I've said much the same thing about Linux Desktop GUIs in general. "It's like they were made by someone who's only ever had a GUI described to them in an email". Compared to a system like the original Macintosh or RiscOS that thought hard about how to abstract things for a graphical display and a mouse, or even Windows that just copied as much of that as they could get away with, it's really quite terrible.