I'm not sure about HTMX, but this kind of behaviour is what Unpoly https://unpoly.com/ excels at
I played with it recently and it was pretty easy to enhance a completely non-js CRUD type app and have it fall-back gracefully. Seems a similar concept to HTMX but has a more batteries included / high-level approach.
I'm in the early stages of an Unpoly project and I'm happy with it so far. It's nice to have things built-in like modals and attaching data & logic to incoming elements. Feels like I have less need to integrate with Alpine.