Supposing hypothetically that this were true, would it still be immoral?
So, until a scientific study proves that women's brain account for them liking dolls instead of Lego, I will still think that's society that makes them that way.
So it's immoral to make decisions based on people's actions if those actions are not proven to be driven by brain chemistry?
Suppose a scientific study said Lego would make more money by selling pink cars to girls and aliens to boys, with no reason given. Would acting on this be immoral?
Or, suppose there were no study, but Lego merely tried out 20 different product lines. Of those product lines, the pink cars sold very well (purchased mostly by girls) and so did the aliens (mostly purchased by boys). Would it be immoral for Lego to continue a sales strategy based on these two successful lines?