a framework using a neat piece of technology isn't really a boon for the framework -- the technology of streaming itself is great, sure, but you can do that with any stack.
also, I find your headline misleading. htmx uses javascript, there's no accessing anything "directly from html". you could say that about any framework with directives, ie vue, but we all know better.
It's an ill-though change for change's sake. Nobody is that impressed.
Flat design was more fully thought. But even that was useless and ultimately user hostile.
"Skeuomorphic" (which is mistankenly called that, few parts of OS X or Windows at the time were actually skeuomorphic in nature) was just better UI.
edit: and I hope not.
I'm avoiding Next because deploying it on anything non-vercel sucks.