Dear me, Angela, you sound as if you have a pretty drastic time of it, quite unlike the s´n´s style which I thought was the new order!
Jokes aside, I think that the reason might be more to do with women using their artistic skills in far more practical directions. I fancy myself as having pretty good colour vision, but I think my wife´s is superior; I have few outlets for visual creativity other than photography - women can exercise theirs in the home or even in the office, given the chance, turning cubes into rooms.
Perhaps it´s to do with spare time, as has been suggested, but then how do you account for Sarah Moon, who moved seamlessly from modelling to photography and went on to become one of the most imitated stars in that firmament; Diane Arbus, flawed as hell in my opinion, but prolific nonetheless?
I guess that in the end it´s mostly to do with compulsion (inner) and the choices perhaps really being greater for men, but that would perhaps have once applied mostly in the professional field and I´d imagine that the LuLa is mainly an amateur´s heaven, not that that is meant to be any sort of derogatory remark, believe me, I´ve long abandoned the notion that all pros are better than all amateurs! But that´s more something to do with women being professional photographers or not, and not really part of the original question of why they seem to post less.
One of life´s other great mysteries!
Ciao - Rob C