I remember Daneel. I had a clear conception of "him" as a male. I don't know if Asimov intended that, but I never doubted it. On the other hand, I can imagine someone who hasn't read Asimov thinking otherwise. Now where are we going and what's with the handbasket?
Certainly some gender roles are learned but there are physiological differences as well from maintaining of body homeostasis to higher cognitive functioning that also predicate gender roles.