Yep. It's bonkers to me that a page consisting mostly of text (say, a Twitter feed or a news article) takes even so much as a second (let alone multiple!) to load on any PC/tablet/smartphone manufactured within the last decade. That latency is squarely the fault of heavyweight SPA-enabling frameworks and their encouragement of replacing the browser's features with custom JS-driven versions.
On the other hand, having to navigate a needlessly-elongated history due to every little action producing a page load (and a new entry in my browser's history, meaning one more thing to click "Back" to skip over) is no less frustrating. Neither is wanting to reload a page only for the browser to throw up scary warnings about resending information simply because that page happened to result from some POST'd form submission.
Everything I've seen of HTMX makes it seem to be a nice middle-ground between full-MPA v. full-SPA: each "screen" is its own page (like an MPA), but said page is rich enough to avoid full-blown reloads (with all the history-mangling that entails) for every little action within that page (like an SPA). That it's able to gracefully downgrade back to an ordinary MPA should the backend support it and the client require it is icing on the cake.
I'm pretty averse to frontend development, especially when it involves anything beyond HTML and CSS, but HTMX makes it very tempting to shift that stance from absolute to conditional.