Peek a little deeper and the reasons are clear. The American philosophy of urban design is broken at its core.
Public infrastructure enables low cost amenities by distributing costs over the number of intended users, ie. residents of said geographic plot. 'Density' is a non negotiable prerequisite for quality infrastructure that won't spiral a nation into debt.
A public restroom can only be maintained if the users/restroom is high. The exact same logic applies to literally everything. There is an inflection point (Mumbai, my home town, being an excellent example of excess density), but no American city comes anywhere close to it.
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I am usually cautious about boiling down complex problems to single causes. But, this one I feel confident about.
Over the long run, nothing has (and will continue to) hurt the US more than the galaxy brained American dream of an R1 zoned car centric town.