I find KDE Plasma to be much better than Windows and MacOS.

Hard disagree. I find that Linux (particularly but not exclusively Gnome) is actually even better than Windows or Mac OS. I hate having to use Windows or Mac again for how clumsy and poorly thought out they are. It took how long before they finally got Window snapping? And file search is still atrocious on both, and getting worse on Windows.

It always seemed to me the people who deride Linux's desktop GUI are those who actually never bothered to use it, especially not seriously in the past decade.

I’ve been using COSMIC for the past month and it definitely doesn’t feel like an afterthought. Unlike Windows, it has window tiling, for one.