The complaining about women's representation at conferences seems to be predicated on the belief that women would be equally represented if merit assessment was unbiased (thus gender imbalance is proof of bias): well, here is a situation where merit assessment is unbiased (performance is measured by a timer). And the gender situation is more or less the same (women's representation is much lower at the top than overall). This leads me to conclude that the women in tech complaining is unfounded.