I think its generally bad, or at least I wouldn't want no part of it. There's decision fatigue for one - how the hell do you decide what to use. Another problem is why would I want to relearn a new framework every time I switched companies? And how do I know these frameworks are going to survive long term in such a chaotic community? I have little doubts Django or Rails will be here in 10 years, can you be confident all these JS frameworks will still be here? Some will and some will probably become irrelevant.