Meanwhile, Gnome just works exactly like you'd expect it to. I said it before already, but Gnome is for people moving from macOS and KDE is for ex-Windows veterans. And, for the record, I don't want to praise Gnome's overly-minimalistic approach, either, which too gets annoying when you have to find an extension for every stupid extra setting beyond the defaults. But, all in all, I much prefer it over KDE and wouldn't switch back. Not to mention the aesthetics, because there's no comparison if one shares the Apple/Braun ideals on design.
A plot twist here is that I am also a KDE app developer...
For comparison, MacOS doesn't have a printscreen key, it's command-shift-3 or command-shift-4. Much more confusing to newcomers in my experience.
There might be a small misunderstanding regarding the "dialog". Once you've selected an area you're shown the outlines & can still modify them, and the buttons (Accept (for further editing in Spectacle), Save, Save As, Copy, Export) are shown below those outlines.
This approach seems objectively superior to your suggestion.
Linux has a DE like GNOME. How many DEs like GNOME does it need?
There's a lot of "we need this" "we need that" in the open-source world. But when you look at all the limitations objectively, we've already reached the highest point we can achieve.
Your whataboutism doesn't invalidate my critique.
Other than that I don't have too many complaints.