Herein lies a fundamental difference in worldview. A liberal would say: well, let people who want to get married and have kids do that, and people who don't want to get married and have kids can do that. No need for coercive social norms. In a vacuum, that sounds true. But a conservative would say: how can you be so sure that those social norms aren't helping people who ultimately want to get married to do so and stay married? The idea that societal happiness is maximized by maximum personal freedom and the total absence of social coercion is not obviously true.
There are life happiness benefits to older people helping younger people know what to look for in a spouse, and setting expectations about marriage and life in general. There are benefits and efficiencies that come from people of a similar age having kids at the same time. There are benefits that accrue from people being involved in supporting each others' marriages. My wife and I got married and had kids in our mid 20s--average for Americans in general but pretty early among our demographic (college-educated coastal urbanites). We didn't realize it at the time, but living in DC/NYC we were pretty miserable. Nobody our age had kids and it was very isolating. We were so much happier after we moved to a more socially traditional exurban place where other people our age also had kids, peoples' parents were actively involved in helping them raise their children, etc.
I think looking at it in terms of education mistakes the symptoms for the disease. Most people obviously had intact marriages back when few people went to college. A college education isn't a prerequisite for stable marriages. The delta is caused by something else that's correlated with both.
This is the thing that turned me away from liberalism after I got married and had kids. In Asian culture, we strongly believe that marriage and families are the purpose of life. Not only that, we believe that society has a responsibility to establish and reinforce norms that encourage people to get married and support their marriages. In my culture, elders get involved pretty intensively in e.g. mediating disputes between young couples to help establish healthy relationships. When I hear "elite" social conservatives lament about the breakdown of norms and social support around marriages, it strikes me as very much in line with how my culture perceives the same issues. And I can't help but agree with them when they complain that social elites won't preach what they practice when it comes to these norms.