"Suburban hellhole?" It's important to realize that many people hate cities, and would much rather live in suburbs. Why are there so many huge suburban areas around (most) large cities in the US?
You have to contextualize those demographic moves.
The post-war American suburban drive was in large part driven by economics and policy. Mortgage subsidization from the 30s with the Home Owners' Loan Corporation and the GI Bill in the 50s made loans available to mass consumers, while the HOLC's discriminatory redlining policy and the deindustrializing of cities (driven chiefly by lowered shipping costs) caused dense urban areas to become less desirable.
Mixed in with this you also had suburban-oriented urban planning (lots of highways, little public transit investment), brand new car driving infrastructure, low energy costs, lots of cheap land to expand to and in the 70s and 80s rising urban crime.
If you were looking to live somewhere, you had lots of incentives to prefer the suburbs. Today, most of these trends (energy cost, crime, job markets) have changed course.
