Your assumption is that there is a "best of class" which can be easily identified and sorted from the rest. Given that most conferences aren't going to consist

Your assumption is that there is a "best of class" which can be easily identified and sorted from the rest. Given that most conferences aren't going to consist only of the absolute paragons of an industry, we can conclude that in planning conferences we're selecting possible speakers from a number of very qualified participants. In industries where there is a grotesque gender imbalance, one way you start to fix that imbalance is by acknowledging it and making efforts to pick women speakers when they're available – that both gives the speakers an opportunity that is being frequently denied them, and it indicates to other women that there is opportunity in this field, that they won't be passed over again and again by men for no merit other than their gender. If we assume that no woman is as good as a man in this field, then your argument makes sense – but that's a silly argument, methinks.