> In other words, the ones who know the most about child rearing (in our culture, that is mothers), are the worst at assessing risk.

Leaving aside the dubious connection to knowledge about child rearing, including the suggestion that childless women have more knowledge than fathers on that point, "most prone to overestimate risks in low-risk situations" is not the same as "worst at assessing risk".

I suspect if a ranking was produced of those most likely to underestimate risk in high-risk situations, you'd get exactly the reverse ordering.