I'm aware that I'm abusing the tool, but I wrote a htmx extension that overrides the mimetype and JSON encodes all the parameters. The JSON is decoded into a data bag on the back end. Basically I can do "fuck it over HTTP"[0] with needing close to zero JS. HTMX has been a god-send to me.
I did something similar, for a dashboard type of web app that involves a lot of graphs. JS graph APIs pretty much all expect data as JSON-formatted JS variables, not HTML.
So I use HTMX to make the server requests, using triggers defined in HTMX, replacing a lot of JS code. It's really only with the JSON-based responses that I'm going rogue. HTMX is so elegant, I feel dirty going against the grain.
[0]: https://twobithistory.org/2020/06/28/rest.html I misremembered the name, it is actually "fuck it, overload http"