It's pretty evident that no one is likely to find a source from Catholic tradition that says that youth and innocence in women means that they are (mentally) too immature for marriage.
It's pretty clear that the idea of mental immaturity of young women is non-traditional.
As Tiffany has mentioned, women who have been single professionals for a long time often find motherhood, keeping house and domesticity much harder than younger women.
It shouldn't be surprising. Younger people are often better at learning than those more set in their ways.
The difference today is that the wider society's priorities for what young people should learn, and who should teach them, are set by those who want birth rate well-below replacement.
The birth rate is getting to the point where one baby is being born for two women in many places.
Apparently Dan Brown's new book advocates massive population control.
That his books have been promoted so heavily shows who is directing society and what their aims are.