Comment by ummonk

One of the issues is that Google is rather reactive in its compensation - e.g. it only provides high-compensation offers to those who obtain competing offers. This essentially ensures that the highest offers go to those who prioritize being able to get high compensation. In my experience, a lot of software engineers tend to prioritize things other than compensation, and don't really care to try to extract higher compensation if they get to do work they find meaningful or work for a company they think is good. And for whatever reason, a much higher proportion of my male peers have prioritized high compensation compared to my female peers.

I suspect that if Google wanted to remove pay differences between men and women, they would need to start making strong offers to all their candidates - not just those who obtain competing offers and try to negotiate.