Essentially, Common JS + NPM lets people/teams create their own "frameworks" with very little effort whilst also freeing them from the bulk and cruft of a framework that has a limited future; if it has any future at all. The tools and technologies we use to create websites/apps are changing at break neck speeds. Frameworks are in it for the long haul and they hope the decisions they make today will be relevant in two+ years time - but devs have to cope with demands in real time. We don't have the luxury of hope.
Here's some good reading http://tom.lokhorst.eu/2010/09/why-libraries-are-better-than...