I don't have any hard arguments, it just seems very counter-intuitive. The ratio of genders is more or less 1-to-1, but one is entitled to much better quality of partners (attractiveness, wealth, social abilities and so on) and also to a much broader selection of potential partners. It's so... implausible. Do you think that women are overvalued on sexual and relationship markets or do you not? If yes, when should we expect the bubble to burst?