Comment by wolfgke

People are free to study what they want. If there are more men who want to study a STEM subject, this will of course lead to a majority of men. Indeed, typical STEM subjects have no limitation on your A-level mark (Numerus Clausus) for being allowed to study it. So there is clearly no selective barrier to entry (Numerus Clausus) [but I'm not a native speaker of English - so it can be that "selective barriers to entry" has a subcontext in English that I'm not aware of].