This comment seems to disregard the point of PG's essay. He's describing a network effect. Just as it's hard to create a startup community (not a single startup

This comment seems to disregard the point of PG's essay. He's describing a network effect. Just as it's hard to create a startup community (not a single startup, as in your examples) you need the types of people who build startups present or on their way. The valley is full of people who are interested in startups and work with them to some capacity. It would be difficult to attract someone interested in startups to move to New Haven when there is already so much attraction to the valley. It's true, you could start a startup anywhere. It's probably going to happen in the valley.