Allow me to propose a mechanism by which this could happen while still meaning trouble:

1. Somehow, men and women end up expressing slightly different cultures.

2. People like being around other people who are similar, because it's easier to predict them.

3. Women avoid men-dominated fields and men avoid woman-dominated fields, regardless of any other reasons or motivations.

The advantage of this model is that it explains the article without invoking any kind of predetminism. (It doesn't even matter what the gender-cultures are, only that they are different!) It also suggests a solution: figure out how to integrate male and female cultures.