That's not the right question. How many highly qualified Google or Facebook engineers would jump for the chance to work at Microsoft if it meant that their salary would double or triple overnight? Suddenly Microsoft doesn't have a tech hiring problem.

Edit: Also, more of our "best and brightest" would choose tech majors (thus qualifying themselves to work at major internet companies) if they paid as much as traditional white-collar professions.

I don't think many (any?) engineers from Google or Facebook would jump to Microsoft for higher pay. If money was the one motivating factor then surely said engineers would be working in finance rather than at Google or Facebook.

I chose Microsoft partly for the money and would do so again.

I know at least one person at Google who used to work in finance and would not have worked at Google without competitive salary.

Thought experiment for you: what fraction of current salary would it take to get a current Googler to flee the company? Would they still do the work for $30k rather than $150+stock?

No company with with an HR department is going to their average employee over $100k without a business reason.