fewer Americans are getting married, but are divorcing less and staying together longer

[Del Tachi]

This is great news for Americans who are married. It means that their marriages will likely be more stable, and their children will be more likely to grow up with two married parents, which provides them the best chance for success later in life.

Not true.  The percentage of all children born out of wedlock in 2016 was nearly 40% - up from 28% in 1990.  The number of kids in foster care has also been hitting record highs in recent years, even as total births decrease (thanks, opioid epidemic!)  Family is not something that is fashionable among educated, urbane Millennials, so the current generation of kids is being born into more precarious situations and more broken homes than ever before.

Whatever is driving this trend in marriage/divorce, the benefits of it are not reaching America's children.

[Del Tachi]

This is great news for Americans who are married. It means that their marriages will likely be more stable, and their children will be more likely to grow up with two married parents, which provides them the best chance for success later in life.

Family is not something that is fashionable among educated, urbane Millennials

seems to be fashionable among Gen Z’s in rural middle of nowhere TN tho 😂

Yup, lol:

the current generation of kids is being born into more precarious situations and more broken homes than ever before

[Del Tachi]

This is great news for Americans who are married. It means that their marriages will likely be more stable, and their children will be more likely to grow up with two married parents, which provides them the best chance for success later in life.

Not true.  The percentage of all children born out of wedlock in 2016 was nearly 40% - up from 28% in 1990.  The number of kids in foster care has also been hitting record highs in recent years, even as total births decrease (thanks, opioid epidemic!)  Family is not something that is fashionable among educated, urbane Millennials, so the current generation of kids is being born into more precarious situations and more broken homes than ever before.

Whatever is driving this trend in marriage/divorce, the benefits of it are not reaching America's children.

That foster care statistic is definitely not good, but I'm less certain on the "out of wedlock" thing. Anecdotally, I know several people who haven't bothered to get married, but basically live as a married couple with children. Also I don't know where you got the "educated, urbane millennials" thing, or the idea that "fashion" drives any of these decisions.

Family is not fashionable among urbane, educated Millennials because its an insanely costly commitment when you're trying to recoup the big human capital investments you made in yourself during undergrad/grad school

Millennials are the most educated generation in history.  When you invest heavily in your education, the only way you stand to recoup that investment is by being a highly-mobile, urbane professional who can relocate to high-earning job markets (i.e., big cities.)  Not only are these places not very family friendly (high cost-of-living, bad schools, etc.) but having to remain professionally flexible/mobile can delay major personal milestones, like marriage or starting a family.

[Del Tachi]

Inequality has become very high, so traditional markers of domestic stability are declining on a similar curve.

Changes in how people marry are actually (probably) the biggest driver of increased inequality and decreasing social mobility.  Used to, it wasn't uncommon for a doctor to marry a nurse or for a lawyer to marry his secretary.  Now, doctors/lawyers marry other doctors/lawyers.  Women attending college/grad school at high rates/working in the professional fields has really stratified dating and marriage along socioeconomic lines. 

People are being smart. You shouldn't marry just cause. Have to be practical.

Getting married as quickly as you can is actually one the most practical things you can do.  Married people earn more money and report less stress than single people, even once controlling for age/education, because a) being able to split domestic responsibilities is actually a huge boon to your professional productivity and b) being married increases your social capital by growing your personal/professional networks (more than 2x, even)

What's unpractical is remaining an indebted, childless renter well into your mid-30s (the rise of this demographic is also, no doubt, a major driver of "inequality", lol.)  Forget love and intimacy, you should marry for the economic benefit of the arrangement  

[Del Tachi]

One thing I will say, as a gay man I'm really hopeful that declining marriage rates will serve as an impetus for conservatives to start thinking of promoting/normalizing same-sex  marriage as a "pro family" position.

If straights are not willing to get hitched and raise kids, I am more than happy to pick up the slack.

[Del Tachi]

Inequality has become very high, so traditional markers of domestic stability are declining on a similar curve.

Changes in how people marry are actually (probably) the biggest driver of increased inequality and decreasing social mobility.  Used to, it wasn't uncommon for a doctor to marry a nurse or for a lawyer to marry his secretary.  Now, doctors/lawyers marry other doctors/lawyers.  Women attending college/grad school at high rates/working in the professional fields has really stratified dating and marriage along socioeconomic lines. 

I imagine women had fewer opportunities for higher education and entering the professions back then. So this may not have been as reliable an indicator of inter-class marriages as it would be today. I otherwise agree with your point on doctors marrying doctors, lawyers marrying lawyers, software developers marrying software developers, entertainers marrying entertainers, etc.

Women attending college at higher rates would be a major driver of decreased inter-class marriages, since college admission/attendance is heavily stratified along socioeconomic lines and those networks drive your professional/social network during your prime dating years of your mid-20s to early-30s