Oh, right. He also specifies mid-level developer (eg. Senior SWE or higher). I assume he means someone who's been working at a FAANG or late-stage startup for a couple years at least; by then, your stock options have started to vest and you can cash them out. Including stock mid-level compensation is usually well in the $300Ks for Bay Area large tech companies.

You actually can pay for rent or food with stock at a public tech company; just sell it immediately upon vesting. Many mortgage brokers will consider it part of your income for the purposes of qualifying for a mortgage. For non-public late-stage companies, you can often get liquidity in secondary market sales; the banks don't like this and usually won't count it toward mortgages, but once it's cash it pays for rent the same as anything else.