In the minds of men, there is a fine line between smart/assertive and nagging, bitching and complaining. Even the dumbest women can nag, bitch and complain, since this is part of the female tactic to control and change the man.
If a woman is acting like a normal person/friend, who is not overselling herself, she becomes more like the woman friend the guy married and instead of what all woman seem to become, when she starts to cross the line in the direction of nagging. The dumb down side of the line, gives that male an opportunity to enjoy his mate/friend before the change women seem to go through into all knowing and all assertive to their mates; yes dear.
When I lived down south a friend said to me, marry a pretty girl, because they all turn into this (pointing to his wife). At least a pretty wife gives you something positive to balance it off. It was not about insecurity to smarts but staying on the other side of the fine line, as long as possible and taking part of this side with you.
Geeze, I pity any woman who has the unfortunate circumstance of being related to you. I sure hope you do not have any offspring that you have infected with your neanderthal ideas. Bleck...