>how societal pressure/approval/disapproval/support/whatever can apply when we are talking about self-study essentially done in secret.

Through implicit or explicit social pressure to do something else other than play with the computer?

I mean, I'm not a girl but even I felt that. I reckon it would have been even stronger were I were a girl.

I doubt girls and boys would be left alone to pursue solitary activities in peace in equal measure.

This isnt "the left", this is just tacit recognition of reality.