The point they're trying to make is that you have very little evidence of that. Specially since girls of under 1 year old are already being surrounded with girly themes from their parents. They grow up being fed girly toys and mentality. Before a girl can even understand what a "toy" is, she is already surrounded by dolls in pink dresses.
So it is really the girl's interests that differ from the boy's interests? Or is it their parent's interests being pushed to them? You don't know this, and you have absolutely no evidence to indicate that it's their born interest to like one thing over the other.
The question is interests. Why aren't they as interested in pursuing careers in those fields? Maybe we are just a bit different in that regard.
And as for your theory on gay people in tech, I am not sure what you're saying. And not sure why you're even mentioning it actually.