Because it's a bullshit article claiming all American cities are shit when really it's just San Francisco and the liberal elite that are fucking up their own cities. New York as well. The rest of us are doing just fine actually.
This is true. American urban design is hot garbage that fell off a truck, went threw a sewer, was dried out, set on fire, and then shot into the sun.
But affordability wise, yeah it's mostly the super-successful liberal cities that are really feeling the pain. Though all the other cities still have serious problems with economic segregation by neighborhood, generally.
Almost all conversation regarding housing / urban design seems to be focus on San Francisco. The only other cities ever mentioned here often are New York, Seattle, or London. So if you live in a reasonable city that doesn't have housing problems, insane tax policies, or homelessness taking over the streets you won't really get much conversation.