Not like he is suggesting that a 40 year old should marry a 15 year old. All he is suggesting is that marriage at a young age is ok and perhaps preferred.
preferable to serial partners without commitment? Possibly leading to a real offer to -gasp! - move in!
Having a child - moving out - onto the next partner?
Chilhood being delayed to where 30-somethings are still “kids”??
If this is where he is trying to direct the conversation - I think it would be an interesting one!