[Samathy]

A lot of young boys wouldn't care at all and would probably enjoy sewing, baking and other traditional 'girly' activities.

Its the dad's with fragile masculinity and out-dated opinions that would stop them going or teach them that those activities are 'girly'.

[fastball]

That kind of thinking results in an inevitable chicken and egg problem.

How did society get this way if it's all a construct? A secret cabal decided what constitutes a "masculine" activity and what constitutes a "feminine" activity, some indeterminate amount of time ago?

If I only like playing with toy cars because my father liked playing with toy cars, and my father only liked playing with toy cars because his father liked it, who was the first father and why did it stick?

The reality is that men and women have different biological compositions with different hormones and different instincts that organically give rise to different behaviors. Sure, toys are toys, and generally any kid will probably be happy with any toy, regardless of gender. But the idea that preferences in childhood development didn't arise organically is honestly not founded in reality.