>>I think the right way to express is that it used to simply be understood that they'd get married, and now both the boy and the girl get to make a choice about that.

Right. These days there are urban subcultures in most developed world cities where most everybody under the age of 35 had little if any contact with an identified father, or even with the concept that there might be such a thing as male involvement except for overnight visits to mom. Obstetricians quietly report maternal ages descending into early rather than late teens (13 and even 12-year-old mothers) with a bizarre systematic turning away of authority's eyes when clearly the situation involves statutory rape. Grandmothers aged 26 no longer cause a blink of an eye.