> By using React, you embrace building applications with a pattern of reactivity and modularity, which people now accept to be a standard requirement, but this was not always obvious to early web developers.

This is quite a whopper. For one thing, the web started off reactive. It did take a while for a lot of people to figure out how to bring that to client-side rendering in a reasonably decent way (though, I'm sorry, IMO that doesn't actually include react). Second, "modularity" has been a thing for quite some time before the web existed. (If you want to get down to it, separating and organizing and your processes in information systems predate computers.)