[astazangasta]

This is incorrect, in my opinion. FB and Google are where capital is currently concentrated in the software industry; therefore, they are able to hire a lot of the top software talent out there. This talent is responsible for pushing the industry forward, and it often does so in a manner that is largely company-agnostic. This is why we get React help pages telling us to use Enzyme from AirBnb for running tests - because the work is being done by software developers who are building general infrastructure for the web, and who would probably end up doing the same basic work regardless of who was paying their salaries.

It's best to think of Silicon Valley as two entities: a mass of technology workers who build software, and a financial extraction function that attempts to extract value from the work they do.