About 15 years ago I first heard that men generally have higher standard deviation than women over various measurable properties including IQ. I didn't know it was controversial until Damore's controversy at Google in 2017.

I still think it sounds highly plausible, since I didn't hear of any studies that would disprove it (links are appreciated).

If true it would constitute a benign at least partial explanation for men/women imbalance in some professions.