Samsung does more for android than Google does for goodness sake.
I agree with you, even when I dislike One UI… I think Google although simpler is more of my liking… But oh boy stock AOSP is so limited that for some users it is even too similar to iOS, with the distinction that you can sideload easier (for now).
Lots of features that Google releases each Android iteration literally have been here in One UI, MIUI, Color OS you name it.