htmx is a great idea, but it's not necessary anymore. We're very close to invokers being baseline (and even that is just an extension of the "composedPath includes -> invoke" pattern), and that will take care of plenty of what htmx was designed to do. Between features like that, and web components, I'm very happy to stick with "plain HTML" (no frameworks; my web components do not draw from a core module or anything).
Also, just a suggestion because it's not technically wrong:
The example of sometimes needing an auto-completing search box is probably not the best one to use. I'm sure it's meant to say "you want the results to be queried from a server/database on every input", which you would certainly need javascript for. But the specific example of just having a search box autocomplete can actually be fulfilled with a datalist element. It won't dynamically re-query results, but it will filter based on input. So it's a muddy example, at best, and that's probably not great for the point trying to be made.