[ghaff]

Arguably, it took young college-educated professionals increasingly wanting to live in cities to make the change. Which in Cambridge/Boston's case led in part to the development of Kendall Square and the Seaport.

Before that, pretty much all the technology-related companies in MA were out in the suburbs and I can imagine new grads thinking if there were going to be out in a suburban office park anyway, why not be in California?

And, yes, historically there have been east coast vs. west coast stereotypes that doubtless have some basis in reality.