Backbone provided some useful stuff for working with collections, a router, and, perhaps most importantly, structure to your projects. You have to look at it i

Backbone provided some useful stuff for working with collections, a router, and, perhaps most importantly, structure to your projects. You have to look at it in the context of the time it was written - it predated React, for example, by a number of years. It was lightweight and the code was easy to follow, the documentation was good, and the API was certainly very stable. Nested views were problematic, undeniably, and did lead in the real world to a big old mess that wasn't much better than the jQuery spaghetti it was intended to replace, with events bubbling all over the place and unnecessary re-rendering and so on. I led a team that built a big Backbone app, back when it was very much in vogue, and it was certainly hard to get this stuff right in practice - perhaps not impossible, but harder than one would have preferred.