This sounds conceptually similar, albeit maybe more similar to React Server Components? I’m really not familiar enough with Phoenix to get that specific though. Even in the JS ecosystem there’s a lot of nuance between seemingly similar approaches (hence why even commonly referenced concepts like hydration can be confused for what they actually do).
I think what Fresh is doing now is more similar to Server Components, shipping full components to the client. With LiveView, once it's set up on the client, the updates it sends over the wire are much smaller. https://fly.io/blog/how-we-got-to-liveview/ shows some examples of the idea.
