Its not evident to me that that is really a concern when datastar is so small, and most of the js is written inline.
Moreover, htmx can only do a fraction of what datastar does - you'd need to add on something like alpinejs to be able to try to fill the gaps. Both combined are much larger than datastar, and not nearly as integrated.
It’s a concern because I use htmx for loading and updating resources and I want those operations to work as well as possible even without JavaScript. I’ve never felt the need for Alpine.js, I have very little I need to do with custom JS, and it’s trivial to maintain that by hand.
Moreover, htmx can only do a fraction of what datastar does - you'd need to add on something like alpinejs to be able to try to fill the gaps. Both combined are much larger than datastar, and not nearly as integrated.