DY. Another problem with the Age Gap Theory is that it does not account for the fact that the population has been growing for three generations and the norm has always been for boys to marry younger girls, just ask your parents and grand parents.
This is not a problem with age gap theory, it’s a problem with your assumptions. This has been addressed numerous times, I can link to the discussions in the cr if you’d like, but first tell me: which time period (decades) are you referring to?