Quite often in my day to day web projects i use the following MaterialUI mainly because it actually employs a nice design system and logic to it; Plays nice with React; There's an edition for every framework; and has a lot of well maintained supporting libraries and examples.
Another fairly complete competitor is
and the quite popular
the one i have yet to use but is still on my radar
On the minimalist front we have:
and then to the extreme we have