We're using our own protocol right now - haven't really looked too deeply at the Phoenix protocol. We use templates (like Solid or Blockdom) to build and patch the page which is pretty specific to Dioxus.
Cool. We went with re-using/adopting Phoenix's because it is battle-tested and allowed us to not have to rebuild/find edge cases on browser event handling and DOM morphing and optimizing diffs. If you ever want a walk through lmk.