1) That's not white collar tech jobs, that's ALL jobs in SF

2) That's base salary, not inclusive of other comp like stock and bonus

3) Benefits are a huge slice of the compensation pie: insurance is not cheap, most companies 401k match, etc

4) Payroll tax is a big chunk too

5) There's overhead associated with hires. At a minimum they get a laptop, but if they're onsite you have to furnish a cubicle and pay all associated costs

Fully loaded, the annual expense of a generic tech hire in SF is definitely more like $200k