I don't believe that higher salary expectations is the solely reason to leave a developer job. I question if there's the main one, because the non-inclusive environment in the industry certainly takes a big role. A high percentage of women drop the industry before the age of 35, not only because they face troubles managing this type of career with parenthood but also because the lack of opportunities and the biased treatment they receive become unbearable. For BIPOC and LGBT+ people is even worse. It's natural that people start to wonder if they really want to insist in a career where they don't feel welcome.