When my dd was little I bought her sand pit, toy garage and tool kits (as well as dolls, prams, tea sets etc). As she got older I got her science kits and techno lego as well as arts and craft sets. And when my ds was little he played with his sister's dolls and prams and tea sets and enjoyed her interminable rainbow fairy books as well as her lift the flap how machines works ones. They both equally enjoyed dressing up as firemen, vets and princesses.
They are still children so not long ago. But I can't believe my children, and those of my family and friends were unusual. Sure households with just one sex tended to have less of a mix of toys but they all happily played (appropriately) with dolls or nerf guns when given the opportunity. And nurseries encouraged this (well may be not the nerf guns).
Is this not still the case?