Yes, there's definitely philosophical alignment with the hypermedia approach: keeping things simple and leveraging HTML's native capabilities. In fact, I use hypermedia-oriented techniques on all the dashboard pages in the Hyperclay web app.
But in Hyperclay apps, the DOM is the source of truth -- there's nothing else. So there's no need for more than a single AJAX call (to save the page). HTMX is built to support a more traditional multi-page stack, whereas Hyperclay is built around single-file HTML apps.
The idea is that every HTML file is its own visual tool for modifying its own UI/data. For instance, you could build a page layout editor that lets users drag-and-drop components, and the editor itself would be part of the saved HTML file. An infinite variety of visual tools can (and will) be built on top of this structure.
As for essays about this vision, I'd recommend "Local-first software" [0] and "Malleable software" [1]