Certainly the distributions of ability in math and math-heavy subjects for males and females overlap. Some women excel and some men are poor. But it still may be possible that the distributions have different means and standard deviations. It is a scientific question and not a moral one. No one is saying that women should be discriminated against and "written off".
When narrow differences in math ability are being used to explain enormous differences in STEM participation, the data does not support the hypothesis, so it's not a science question, because it's not science.
If the narrow differences are being used to justify a social engineering outcome whereby one group is being subverted and undermined, then that is indeed a moral question.
I am encouraging my daughter, just not making a special effort because she is a girl.
All of my children did EPGY (often while sitting on my lap) and now attend Russian School of Math. I often help my children with RSM homework and quiz them on math. My wife and I encouraged our daughter, now in 6th grade to attend the math club. She did for a while, but she never made the team in tryouts and has stopped going. She prefers other clubs, such as running, volleyball, gardening, and art. My two boys do make the math team and are enthusiastic mathletes. My daughter gets straight A's and will be in top track math in 7th grade, the first year that math is tracked. I expect that all my children will take AP exams in calculus and the natural sciences before graduating.
You can expose children to things, but they will decide what they like and are good at.
This outcome would be consistent with the study I linked upstream (see response to aeh) which correlated the father's attitudes to math outcomes for the different genders.
