Those who survived this filter tend to be less of the tech fan boy culture.
Of course being a girl had a special status, there's just no way around that when they are below 10%. There were many cases when a class had only 1 or 2 girls, or I remember when the game design class had their first ever female student, whom I knew. She didn't recall any inappropriate things said to her. But you have to have a really strong interest in the topic to accept being the only girl in so many situations and groups. Just "going with the flow" won't carry you there.
This whole thing must have some deeper roots than what it's being reduced to today, because the effect comes up in many countries even before US influence became this strong. In fact in the former Eastern Bloc countries there was a lot of encouragement for women getting educated and getting more traditionally male jobs.
Perhaps those fields are perceived as not social, introverted, not warm or inviting; but I feel it would probably be a bad idea to market them as such and force a lot of young women into engineering and CS out of some misguided principle rather than their own future happiness.
Of course there are certain men that make claims about women's ability to do math, but in my experience those are often men that clearly don't possess that ability themselves... Their opinion might be mostly detrimental to their own offspring rather than to society as a whole. Those tend not to be people whose boys attend university either.