Male on female sexual harassment is worse per female capita (which is the effect people complain about, whether the realize it or not) wherever women are a smaller minority. This is basic math. It isn't anything special about SV culture beyond that. The base rate of male on female sexual harassment varies locally due to accidents of cultural background history. Having females in positions of power can likely help with that, so it is all tied into the virtuous/vicious cycles that relate to gender imbalance.

And techie women are better than average of raising awareness of problems in their industry, because they know how to Internet.