If you can only make 150K in San Francisco, you'd be better off moving to a MCOL or LCOL US city where you can make nearly that much and have no trouble paying rent. It's only worth working in San Francisco if you're making 200K+ and think you have a good shot at making 300-500K in ~5 years or so (or if you're already making >300K, obviously).
When I made ~$150k in SF, that equated to $8k/month after-tax. $2k/month for a decent studio/1-bedroom apt near Golden Gate Park. I felt very comfortable and very much enjoyed my quality of life on that salary.
The actual number is irrelevant; If you make <roughly average amount> in SF, and pay <way over the odds> for rent, post tax and rent, your leftover money is still more than a mid level engineer in Europe, even in London where the costs of living are proportional. If you make 2/3/500k it only skews in the balance of the bay area.
