You skipped a huge step. There was angular before react. Which was horribly bloated and over complicated. People wanted something simpler. React, with it's facebook clout won in the end.
Something more simpler: Svelte
Just try it and give it a chance.
I personally heard that 'objectively better' line incessantly from 2015 onwards, with 'it has the largest community' always being a top highlight. Facebook's backing and the celebrities that developed in the JS community around the time certainly played a part in it.
I was working at Groupon and using Backbone at the time and found nesting components to be a major hassle. We used a framework called Thorax on top of Backbone, which helped but still fell far short of React's convenience.
That's not what I intended to say, of course that's not the only reason people choose React, but I think they are valid reasons to help you decide.
For example let's say two libraries are technically different but equivalent productive and nifty, choosing the one that has a bigger ecosystem is a totally valid choice.
Many people had to sell React to their bosses, and the fact that there was a presentation by Facebook, helped a lot, I don't see how stating the obvious is calling lemmings to anyone.
At the end of the day, it depends on your goals and motivations, I can't talk for everyone, I was actually saying some of the reasons that helped me decide on choosing React.
Go watch the original React debut talk and ask yourself if React had/has anything going for it beyond Facebook's backing. I know I, and most developers I know, dropped Backbone/Knockout/whatever instantly to use React because it was so obviously better.
Now that unidirectional flow is the state of the art, the difference between the main frameworks just isn't that big. You gain a few things here, lose a few things there, and write a solution that is similar to what you would have written with the other frameworks.