Hmm, here's a thought from a different angle.
First women have had a BIG effect on sailboat design in recent years, probably more than those America's Cup racers.
Why? Because production boat manufacturers recognized that wives have a big say in the purchase so they started asking what was important to them. They found women had different priorities than men and that influenced design.
So if manufacturers are catering designs to women why are their fewer women owners?
Well first couples outnumber singles by a pretty wide margin in every marina we've been in.
But maybe the reason you don't see more single women owning sail boats has as much to do with marketing as anything else. Boat manufacturers only advertise in sailing magazines, mostly read by people who already sail.
Maybe advertising outside the sailing rags would bring new people into the sport. Since half the population is female - well do the math.
BTW, for us sailing is a reason to spend time together and that's a good thing.