At my previous company, it was very easy to move from SF to Seattle, which would save a high income tech employee a lot (no state tax, lower housing costs). Maybe a dozen have moved; the vast majority haven't. These "revealed preferences" say a lot more than what people are claiming.

Honestly, at high enough levels in top tech companies, money isn't that limiting of a factor. e.g. at Google L7 level, an employee supporting a family (say spouse and kid) could have FIREd into a low-COL area after ~5 years of work.