It also doesn’t show, at any point, that it’s required.

There’s no magic abstractions going on. Everything is regular html elements. You can just use the regular js api.

Reading the docs and having an understanding of how frontend works would give you that information.

What do you think the link to attributes on the front page does?

What do you think the whole reference is about?

What do you think the docs that use and show all that do?

> Reading the docs

https://htmx.org/docs/

Literally the first example uses htmx's DSL:

  <button hx-post="/clicked"
    hx-trigger="click"
    hx-target="#parent-div"
    hx-swap="outerHTML"
  >
    Click Me!
  </button>

The only place where it talks about anything else is a small section on scripting with a link out to a huge meandering essay with small examples lost in all the philosophical discussions.

Edit: Don't forget also that this is entirely non-optional because if you use htmx, you will load the full support for it whether you use it or not

The example provided is not hyperscript.