In my parents' day, "finding a husband/wife" wasn't something most people had to make an active effort in order to do. It happened fairly naturally. So smart people paired off at a similar rate to everyone else.
In the post-"Game" world, wherein breaking through womens' defenses and attracting them requires learning a bag of cheap sales tricks, the big losers are the people who don't learn them. These are the dumb, who are unable, and the smart nerds, who can't be bothered because they find childish social games uninteresting.