Eh, honestly with GNOME ymmv. Many API breakages, most recently with extensions in version 45. It's also not very light. GNOME's UX is also quite opinionated but some people like that.
I just use gnome, I am sure other desktop environments suit others better. But I know gnome just works. Windows and MacOS have the same issues you pointed out with gnome though.
With popOS maybe, but I would never hand Ubuntu Desktop to a non-dev. I can't remember the last time where it properly installed (including getting NVIDIA drivers working) without using the terminal.
Yeah no. You often need to install extensions to get icons on the desktop etc., which break when you upgrade Gnome. Talk about user-hostile design.