Earlier quoted context omitted.
A developer in SF is not in the upper quintile.. they can't even afford a starter house. Big cities add huge costs that start making sense with home ownership but will leave a renter worse off. Good advice on the other points.
The median household income in SF is $92K. https://sf.curbed.com/2019/2/25/18239828/report-middle-class... The average software developer in SF makes more then twice that. https://www.builtinsf.com/salaries/dev-engineer/software-eng...
https://www.census.gov/quickfacts/fact/table/sanfranciscocit...
And that's of 2020 so out of date.