Those are huge companies with tons of cash. Referrals are less important when thousands of college graduates are stampeding for a job at a tech titan. Also, how much of the upper management at either is Indian or Chinese?
Google's CEO: Sundar Pichae
Microsoft CEO: Satya Nadella
Adobe CEO: Shantanu Narayen
It is true, though, that Chinese people are underrepresented in upper management.