Silicon Valley has been a playground for venture capitalists and their beneficiaries but I would wager that their influence, while wildly public and social, is only important inside it's bubble, and much of that influence has been frivolous, bought or self inflated. Does anyone really need Facebook or Twitter, or Hootsuite or Gmail? They have only existed for circa ten years each.
So I don't believe it's the beacon of social benefit or industrial power. It is certainly a beacon of wild capitalism, excitement and glamour. Whether that's a good thing or not is hotly debated, but a world without SV unicorns would move on just fine.