Well then why do the people who do earn that much there need it?
It's also a vicious cycle: high tech salaries in those areas have driven up the cost of living.
The prices in Madrid/Barcelona are not exactly far off already (through no fault of high tech salaries).
Not on the West coast, no, but my contention is that my comp when I worked for a FAANG in Seattle (5 years ago) would put me well into the top 0.2% of Spanish earners