I ran a web dev company for decades. There are two web sites we created I would bet money you have visited so we weren't a small, one-off shop. We had never seen the need or desire to use React. We couldn't understand why anyone else would use it either. It was too big and too complicated versus just using the fundamental elements of programming for the web. So there.

Counterpoint: I'm currently employed building many apps for an enterprise you'll never visit. React+Typescript rewrite of our legacy "lean" Javascript has measurably improved the productivity of the team and the maintainability of code.

I can't imagine going back to learning bespoke libraries written by (especially!) hotshot cowboy coders. React makes everybody on the team better, and literally no customer has ever complained about the extra 200ms load time.