As I said, there is a vast overlap between boys and girls. Boys even do better in some subjects, notably mathematics and (some) sciences[1].
In the same way that if we streamed per-subject, there'd still be a significant number of girls in the top set for maths, if we streamed by performance overall, there'd be a lot of boys in the top schools.
Nothing about streaming implies gender segregation, so I'll ask again: do you have another reason for being against it?
That's why I wrote "generally". There are many countries, subjects, and years of education to compare so you can always find some statistic that bucks the trend.
In the same way that if we streamed per-subject, there'd still be a significant number of girls in the top set for maths, if we streamed by performance overall, there'd be a lot of boys in the top schools.
Nothing about streaming implies gender segregation, so I'll ask again: do you have another reason for being against it?
[1] https://www.theguardian.com/education/2025/mar/10/boys-widen...