The obvious (paternalistic) answer is that they believe that, conditioned on them being born female, their self-interest is improved by paternalistic treatment of all women vs equality.

In order to convince them otherwise, you would (at a minimum) have to run multiple world sims, not just multiple placements in one world. You would also have to forcibly give them sufficiently rational thought processes that they could interpret the evidence you forced upon them. I'm not sure that forcibly messing with people's thought processes is ethical, or that you could really claim it was a coherent extrapolation after you had performed that much involuntary mind surgery on them.