I've been looking at this from a slightly different level. React may be the best choice for a UX on the web but I think it's still far worse than any native app. It's one of the reasons I get so disappointed after hearing about something cool and new and then finding out it's an Electron app.
I'm stuck on this idea that the best UX is a native app for performance reasons (responsiveness, memory, CPU, battery), aesthetic reasons (assuming your like your native platform) and longevity. On my desktop I often run applications that are a decade or more old. How many web apps rolling out today can sit untouched for the next decade and continue to do useful work?
I haven't done it so much lately but a couple years ago whenever I would check an app with nice UX it was React, and if it was terrible UX it was Angular or something else.
Also interested to see where Svelte will go. For my latest project I just didn't choose it because of lack of libraries.