I agree for the most part. Collapsable dropdowns and jQuery drag-and-drop are nice-to-haves, but I also clearly remember the hellscape of state management in js/jQuery and I'm not to keen on going back to that.
The problem, from what I saw was nested forms and trying to hold state on the client when the server should have been asked for the state. This lead to template duplication and trying to hold too much state on the client.