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[Statilius the Epicurean]

People choose to live in cities because the most prestigious and high paying jobs are there. I'm not sure what "rethinking urban densification" would mean other than incentivising companies to move to less dense areas, which would destroy knowledge clusters so there would be fewer of those good jobs to go around in the first place. Sounds bad.  

I don't think your OP really grapples with why cities exist in the first place. It's not because of dastardly urbanists forcing everyone because they have failed to "rethink" as you want them to.

[Statilius the Epicurean]

This is a ridiculous assertion. People live in cities for many reasons, not all of which qualify as choices. I don't know how anyone who has spent so much as five minutes thinking about cities could believe something so reductive.

In aggregate employment is the driver of population. Why did San Jose's population double from 1980 to today? Because of Silicon Valley providing a cluster of well-paying jobs. Why did Buffalo lose population over the same period? Because manufacturing declined. Why did the United States go from 40% urban in 1900 to 80% urban in 2010? Because agriculture shed jobs to services, that cluster in cities. Why is Manhattan so dense and expensive? Because Wall Street is located there.

If a city stops producing value, its density will fall:



I suppose we should congratulate Detroit for "rethinking" urban densification.

It sounds like you lack imagination. The point of reconsidering urban density in the United States is exactly that, to think about the subject, especially the assumption that living in a place with greater population density is bound to be a positive change for those involved.

I don't know what this means. Quite frankly it reminds me of a contentless slogan like "reimagine the police". Like ok you have a poor opinion of the police, now what? If you have an argument, make it.

Whether or not one thinks population density is great in and of itself, it's the product of millions of individual choices. Cities are dense because millions of people want to live in them, and people build houses to accommodate the wish of many people to live in them. Insofar as urbanists promote density, it's so that people can afford to live where they want. And the wealth of the modern economy is driven by the value-added of these dense clusters of people.

It might be the case that density will reverse itself due to WFH becoming more widespread so people don't have to live near the office anymore. That would be great. But I'm not sure it would be the result of a grand "rethinking" of density as a concept.

[Statilius the Epicurean]

This is not a policy argument. It's not even a piece of advocacy. It's just a challenge to an increasingly common assumption about how the country will change in the coming decades, i.e. that more children will grow up not caring about owning a house or a car, or, at least, content to live without them.

Your challenge is "density is unhealthy", which everyone knows. The point is that density is unhealthy and everyone knows it, and people still move to dense areas in droves. Why? Because that's where jobs are. Simply pointing out that cities have smaller housing than the suburbs is just banal, unless you grapple with why people accept that inferior housing. 

That's why I mentioned WFH, because if that becomes widespread and people can get good jobs in the city without having to live there, many people many take advantage of it and density would reduce. Of course we don't know the extent of the impact that would have. It could turn out to be minor. But that's a more interesting and plausible mechanism than QoL disparities that have been around forever.