The reason why Silicon Valley works is because of the intense greed that it provokes amongst everyone that comes here. Maybe "greed" is too strong of a word, because people aren't necessarily selfish, maybe "money-focused" is probably more accurate. And because anyone can come here and become a millionaire/billionaire, it draws in an immense number of hard-working people which just generally increase the level of competence, and unfortunately competitiveness, which has a positive feedback loop which causes these smart people to want to work even harder over time.
Outside Silicon Valley, all you hear about is billionaires being made day-after-day, and smart people they look at this nonsense and think "I can do that". Once the come to Silicon Valley, they get sucked into a vortex of work and money-focus that is so strong that the only way to get ahead is by working long hours and taking risks.
Think about it this way: a person who makes 120k/yr with 2 kids and a spouse who stays at home will be considered the "working poor" here. I feel sorry for anyone who tells me they have a spouse, 2 kids and a house in any place other than NYC, and are contemplating moving to the Bay Area. Everything is priced perfectly to the point where no one can afford to live in a good neighborhood with a good commute with good schools. It's like the CAP theorum, except it's more like "Good Job, Good Neighborhood, Good commute: pick one" (unless you're rich).
So, in order to get ahead, both spouses need to work, and they need to work very good jobs with long hours in order to "make it well". If you have Dual Income No Kids, it's a bit easier, but you still need to deal with oppressive traffic and high rent. It's so expensive, that all you do is think about money. And you fall into fallacies where if both spouses make #120k/yr, for a total of basically $250k/yr, you start thinking "why don't I feel rich?" or "why am I working so hard with nothing to show for it?" It's because you work 10 hr days, and then you're spending 2 hrs a day commuting, and you get into a zone where all you do is think about work, and how to buy the next iPhone because at least you have something to show for your money. Meanwhile, none of my friends outside of SV have iPhone 6's let along iPhone 5S's, many are still using iPhone 4's which are perfectly good but a bit slow, but you wouldn't be caught dead in SV with one of those relics.
So all of this money-focus necessarily squeezes out as much productivity from the best and smartest in Silicon Valley, which is why you have so much success here. If you compare SV to place like Japan or China, where the population is generally better educated, you don't get anywhere near the same level of productivity. In Japan you get high prices and long work, but there's no payoff like there is with Silicon Valley because of the social impedances, so you'll never have a Silicon Valley in Japan. In other places that purport to be another SV, even places like Austin, there just isn't the same level of greed/money focus like you have here, so I don't think you'll be able to get as much productivity. It's the sky-high prices, work-life imbalance, the startup-millionaire stories that create this unique pressure cooker environment that can't be duplicated.