There are many, many more places outside SF with a high(er) standard of living and about zero risk of being unemployed as a developer. Most of theses places outside the US also have decent social security, public healthcare and other facilities in case you should fall through the cracks at some point. (No amount of ninja rockstar tech skills will protect you against getting burned out or other misfortunes.)
This ignorant exceptionalism is something I really hate about these SF/SV types. I guess it illustrates why so many stick around: not because it's so great, but out of uninformed fear.