Users like me who got annoyed by never being able to easily select the wanted image (when in a gtk app), for many many years now, had no insight into any architectural changes or code cleanups of gtk4. So there weren't any complains from this group there.
This is the typical "everyone is against us" you often hear from the gnome side. It's a shame to read this under such a nice release, which has only positive changes as far as I can see, it really seems to address a lot of the criticism in a good way.