This isn't about high positions. This is about choice of profession. I can buy your argument for why men become CxOs (although based on people I've worked with in the past who have said they'd never report to a woman, I think sexism plays a large role in our industry), it doesn't explain why women as a whole go into poorer paying fields.

Psychology is the classic example. Few women in the field in the 60s, and pay was relatively good. By the late 90s it became dominated by women and the pay dropped signficantly. Did women go into because the pay was low, or did the pay drop when women went into it? You can find people who argue either side.

But the point is, there's never been an industry that women have gone into that has become a high paying field.

The best way for your son to be a financial success is to not go into whatever his sister is going into. :-)