HTMX is a solution of a problem like the following: how to add small bits of server-based interactivity to an otherwise static HTML page?
One way would be to go with React, Nest.js, setting up SSR and hydration of just the right fragments, etc. Another would be to take your existing static HTML page, and add very few bits in a specific place.
An easy example: a "like" button + counter of "likes" under a blog post.
If you need a complex SPA UI, you need a different tool.
So you're talking about a page where the results are generated according to what the user asks for at the request time, but doesn't otherwise need to change.
If it were a blog, or a corporate info page, I'd rather use a CMS. That way I don't write HTML at all. It would just hand me minimal interactivity.
If it were a shopping site, I'd probably want more interaction than just a single "like" button. I'd want to filter results, sort them, edit a shopping cart, etc.
It doesn't sound appropriate for visualization. It might be useful for a dashboard, but the more people expect to interact with the dashboard, the more likely it'll tip over into SPA territory.
I'm sure there's a niche, but it feels kind of narrow. It's complicated enough to require programming, but not complicated enough to require an SPA.
