Maybe this is a side effect of this current day and age being a specialist society? Everyone needs something to differentiate themselves from the crowd, and Javascript being such a recent growth in setting a "standard" with regards to frameworks and tools makes for a good incubator for specialists.
This is precisely how I see the ecosystem too. If I've learned anything:
1. Focus on something —Rails, Python, Javascript, WordPress, something 2. Learn to actually program — any language will do