He knows that what he's said has been said a thousand times before, and he knows that every time it's said a bunch of people will reply with "separation of concerns, not seperation of technology", and he knows that's a very valid counterargument which can't be refuted in a tweet, which means he also knows how pointless this is. Which in turn means that he's not doing this to start a discussion, but just to get a rise out of people. Giving him the benefit of the doubt, he might actually have an interesting point to add to the debate...but we'll never know, since he thinks a better use of his time is trolling React developers than actually making his case for...whatever it might be.
One of the tweets in reply to him hit the nail on the head: https://twitter.com/chrisbarless/status/810918115601158145
Sad.
Edit: Scroll through Fuchs' twitter feed right now; he's basically just non-stop trolling. "This is why we can’t have nice things" "Q: What is React? A: It’s PHP, but on the client." "I can see how react is awesome if you build todo apps that do nothing. :)" Then when noting how a million people are disagreeing with him: "I think that means that I’m on to something." No attempt at dialogue, no acknowledgement that there might be alternative viewpoints. Almost every tweet is another dollop of smug arrogance.
It must be nice to have so much confidence that you never have to stop and wonder if there might be something new you don't yet know.