Even if this were true, it doesn't mean that men get more stuff done. I' be interested in a study that measures the difference in job performance for equal compensation levels between men and women. Even that study might be biased because there's some evidence that if a woman and a man perform at exactly the same level, men get better ratings, but it would be better than simply measuring hours "worked".
I also think throwing in statements that disparage women with the caveat that "I don't have the facts to back this up" is irresponsible and contributes to the sexism problem.