ofcourse: it will harm the entire family structure. Boys will be getting married even less mature than now, which is already creating a divorce crisis. Also, girls will lose a significant potion of their very narrow window to find a spouse and have children.
Addditionally, if they attend college/work for a number of years post-seminary, they will likely be looking for a very different type of boy. Some might consider this an advantage, but it is certainly a amjor shift that must be taken into account.