Men have a mitzvah of pru urvu so don’t want to marry a girl who is 40. Also, they have issues of hirhurim so shouldn’t wait until they are older themselves.
It could be that it is better for men to get married younger and struggle through a few years of marriage until they mature in order to avoid hirhurim. That being said, if they are at a point where they are still so immature that there is a high chance of the marriage ending in divorce then obviously that would defeat the point.
sm29, I’m wondering, are you speaking from experience as someone who got married young/old? Were you born in 1929 or are you just perpetually 29 years old? 🙂