Have you considered the possibility that your high salary is not entirely due to a shortage of people with the same skill level, but rather because SF/NY companies have too much investor money to spend?

I'm not saying that good software engineers are a commodity, only that SF/NY salaries are too high compared to the rest of the world.

Engineers with 1-2 years of experience in SV can make more than most seniors with 20+ years in Europe. Would you say that's because all these junior engineers in SV are worth more to a company than seniors in Europe?