Agree with @bradlys' comment: This just suggests more highly paid people are being allowed to work remote, vs. remote jobs being paid more.

Given the expansion of high paying roles across geographies, this could be driven almost entirely by FAANG opening engineering / R&D centers in other cities like Denver / Dallas, etc.

Also 'remote' could be laxer standards for these same companies on going down to Mountain View / Menlo Park driven by commute and traffic. Many of my friends commute 2x a week, passing the 50% threshold for remote work, even though I wouldn't consider Menlo Park / Mountain View to SF 'Remote'