According to Levels.fyi - and my personal contacts - https://www.levels.fyi/t/software-engineer/locations/san-fra... Median TC - something just-south of $300k TC (not salary) is more likely.
Furthermore, the higher you go, a greater proportion comes as RSUs, not cash - even if it was $400k TC, a good chunk of that is money you literally can't spend for a couple of years.