Good list, thanks. In what way is it speculated that Backbone would be dying? I've only seen comments here and there asking the questing if bb is still alive, but no actual reason behind it. Perhaps because it's a quite matured framework and has been around for a long time it doesn't get the exposure that newer frameworks do, like Angular2 or React.js
Backbone doesn't change the basic idea behind the framework much, and since it's a quite slim framework, most of the opinionated updates happen in add-on frameworks like Marionette, Backbone.Validation or Backbone.DataBinding.