> thousands of current "Bay area tech workers" grew up in other parts of the country, and [...] may not otherwise share in the religious, political or social views that dominate that space.

I know a few, who grew up in rural Michigan, and Oregon, respectively. But from conversations with them, I get the impression that, while they carry some traces of their roots with them, they also have much that sets them apart from their background (putting a high value on formal education, cultural tolerance, etc).

And ultimately, Bay Area values WERE formed by the people who moved there. Janis Joplin? Texas. Nancy Pelosi? Maryland. Donald Knuth? Wisconsin.