No, that's not true. If it was true, it would mean that the vast majority of the stupidest people are man and the vast majority of the smartest people are man. And the later statement will get you into lots of trouble...
This does however not mean that there is a vast majority in either extreme, rather that if you look for the extreme ends of the spectrum, you will find that one sex is over-represented.
[1]: https://en.wikipedia.org/wiki/Sex_differences_in_intelligenc...
Also, assume that higher risk results in more variance. More of the riskier group will end up on the far ends of the curve.
Now, what happens if the riskier group's left side of the curve is ignored?