Rampant crime, human waste on sidewalks, parks filled with homeless encampments, used needles everywhere, riots, looting?

Not every city is San Francisco

Or LA, Seattle, Portland, San Diego, Detroit, Baltimore, DC, Chicago, Minneapolis........

Essentially, flaws that are unique to and induced by scale and consolidation.

Outside of the current pandemic, those problems range from the rent-seeking consolidation of housing ownership into very few hands, to the elimination of forms of self-reliance that create healthy community — instead shifting those responsibilities to government and large institutions.

Scale also requires more top-down centralized control and regulation in order to function at all.

The issues you stated could be suburban or even rural issues, not just urban issues. In other words I think you might be conflating the difference between an agrarian economy with a modern economy with specialization, not urban vs rural.

I saw a different explanation. Cities are inheriently high density and make things used enmasse as much as possible and inevitably leads to more contact among others. This is unfortunately also a good way for pandemics to travel. The isolation highlighted how little they owned spacewise.

Now that is a spectrum and we are all dependent on others but they are at the high end. The low end is "compound in the middle of the wilderness which is dependent indirectly for there to be wilderness unused for them to DYI everything".

The issue will hopefully wind up rare but there is no great certainty in these matters.