It’s not so much a question of “complexity” as it is as issue of “appropriate use”
that makes so much sense, as does knowing/thinking about the subclassing you described; I hadn’t really absorbed that as a possibility before but it makes sense now that you mention it 
Ummm… I’m going to response with a very cautious “Yes?”. (I’d love to see one or two of the topics to understand the context of this statement.).
There were definitely other related helpful posts that I’m struggling to find again to link here, but the one I saved was Multiple forms/actions in single view. The comments by you and philgyford on that post best describe my confusion – as you recommended to that poster, I too need to separate the concept of a “page” from a “view.”
I’d previously been exposed to the fact that a view takes a request and returns a response a lot while learning so I surface-level “knew” that fact, but I didn’t “understand” it (and I still don’t think I fully grasp it intuitively in practice; I definitely have more to learn).
Unless you’re talking about cases of JavaScript doing an AJAX load of parts of the page, or something similar to that, I’d raise some questions about the accuracy of that.
I’ve watched and read some stuff about using htmx, but I’m very new in this area and haven’t really done anything with JS or AJAX at all