What exactly do you mean by js fragmentation? If that, you have power to pick from hundreds of lib/fw and combine them together, then what you call fragmentation is actual real benefit for me. I like to make decisions myself, but if you like the others to take decisions for you, js is probably not for you. The very good example is redux. Redux was once simple state management lib. Take a look at it now https://github.com/xgrommx/awesome-redux. That is real power of js ecosystem.
Obligatory self-plug: the "awesome-redux" list is cluttered and not well organized, and was actually rejected from inclusion in Sindre Sorhus's "awesome-awesome" list because of that ( https://github.com/sindresorhus/awesome/issues/714#issuecomm... ). On the flip side, I keep a list of Redux-related addons and utilities at https://github.com/markerikson/redux-ecosystem-links that is actively maintained and has (hopefully) much better categorization, as well as being a much more comprehensive list of all the useful pieces out there in the Redux ecosystem.
But yes, as I've said in some recent comments: Dan and Andrew found a sweet spot with Redux's design in terms of approach, concepts, and providing building blocks for others, and that's led to an explosion of useful stuff that people have built for their own use cases.
