The high range of glass door salary pretty much matches what people report on blind for Google eng directors, Netflix eng, etc. It's just that blind salaries after years of stock growth. Glassdoor is pretty reasonable it's just that people inflate.
Glassdoor require you to report your salary to use “Know your worth” service, I imagine people to be truthful to get real comparison with the market.
Salaries listed on levels.fyi seem to be pretty accurate.
They more or less correspond to Glassdoor, difference is Glassdoor requires salary posting so you get a lot of old data for smaller companies.
From talking to my friends at FAANG, levels.fyi is pretty much accurate, at least pay band wise. Dunno about median.