Comment by kokanee

It seems like the author has never worked on an interface that uses realtime UI syncing. The points about cumbersome and mundane issues when working with REST UIs are not wrong, but the challenges of working with realtime synced UIs are substantially more difficult. And I'm not talking about conflict resolution, which can be abstracted by many existing solutions. I'm talking about the intricacies of UI behaviors that are specific to each application, when suddenly every interactive element can potentially be interacted with by multiple parties simultaneously.

For most applications, the status quo whereby a little bit of recent state is maintained locally, and periodically pushed to a centralized store, seems to provide the best overall balance of complexity and functionality. One exception is that most applications do a poor job of actually maintaining the local state (e.g. most forms clear when you refresh the page, which is not hard to fix).