I mean you're not wrong: end of the day htmx is just some javascript written on top of standard vanilla javascript apis. It tries to handle things in a more html-centric, attributes-driven manner than script-oriented approaches do, but it's nothing too complicated

check out fixi for our ultra-minimalist take on the idea:

https://github.com/bigskysoftware/fixi

Or, for extreme minimalisim, htmz, which repurposes iframes for a similar idea:

https://leanrada.com/htmz/