I think you missed the point, this isn't a guys are better than girls thing, he's referring to things like muscle structure differences and the real physical differences that exist between male and female physiology (Can be seen in Olympic Weightlifting when comparing maximum weights lifted by genders). The thing is those differences are overcome mostly by selecting the right training partner and in competition weight classes do well enough to match people.
IMO both yourself and the OP are a little off course here, the difference in physiology don't come into play as much in martial arts for the reasons I've mention and if we ignore the very real physical differences in genders then we run the risk of unsafe competition.