Right. But, hypermedia systems doesn't go far enough. It can be even simpler then that.

In a video game the "server" doesn't figure out what's changed (that's too much work) it just redraws the frame. So rather than the complexity of working out what has changed you can just send down the whole page again whenever something changes.

This gives you view = f(state) over the wire and has great DX. It's called immediate mode in games.

The main point of hypermedia is the browser, not a gaming platform. Not even the mobile platform. HTMX is not purposed nor it advertises that it should be used outside of the browser scope. I use Unpoly that replies on the same principles (HTML over the wire) and both of them are very clear about their intentions.

In my mind collaborative apps are a core feature of the web. Streaming hypermedia is a great way to keep all your state on the server and have a solid multiplayer/realtime experience, especially with large datasets.

Here's a basic google sheets clone that does just that:

https://cells.andersmurphy.com/