While I don't agree with your assessment of privileges, let's look at it in another way: should boys be artificially constrained so that they don't outperform girls (and I am not implying boys would outperform girls, just that that is what society seems to think)? If you offer a robotics course only for girls, but not for boys, this is what you are effectively doing. You may end up with a better gender ratio, by preventing boys from getting into robotics (I doubt it'll work that way, but let's assume it does). Is this the way we want society to resolve this issue? Why not foster everybody's talents?
The idea behind gender segregated classes/courses is about performance, but rather about social expectations and provided a space with less bias than a mixed gender setting. Whether or not this works is one thing, but this isn't about hampering performance.
From the article, it doesn't sound like it was segregated courses. It sounds like there was a single "girls only robotics" class, and nothing corresponding for boys.
I think it's up to discussion how they are 'less privileged'.
Because now you're excluding both classes. Two exclusions don't make a right, so to speak.
Sex based discrimination doesn't help reduce sex based discrimination. Surprising, I know.