In reply to Scott Hartley.

I think it's one of those "If you build it they will come" scenarios. The plugin suffered from a change in endpoints/schema. The first half of core suffered from "Oh well not even WordPress is using it". That being said we have done a lot with the REST API and there's a movement behind some of the stuff that's going to end up in core to use it for various parts of WP's interface. No refreshing to delete posts or save menus... or update posts. Development may seem slow moving, but the hype will come.