In China, women supposedly make up something like 40% of the engineering workforce. Yes, it’s a cultural issue, not a biological one. That’s the point – perhaps those cultural barriers needs to be tackled, instead of blaming the biology.
I taught a computer science college course for a week in China. A full half of the class of 75 students were women. Compare that with the U.S., where I consider myself lucky if I get two female students in a class of 40.