Personally, I'm pretty fatigued at people pointing to disparities as though the cause of the disparity is so obviously nefarious that they needn't even articulate it (as though it's some sort of self-evident truth). I think you'll have a better time persuading people (certainly me) if you make the case that the boardroom gender disparity is caused by discrimination (rather than, for example, differing priorities between men and women in aggregate) or perhaps why (irrespective of discrimination) gender parity in the boardroom is such a significant social benefit that it justifies "positive discrimination".