You are correct about suburbia. There are also typically no sidewalks and minimal shoulders, so even if you live within walking or biking distance of places, it is dangerous to not drive there.
In the US, some of this stems from racism. I don’t feel like getting into the history of it, but if you are interested, red lining, restrictive covenants, and using the cost of car dependency as a racial filter are good starters. Basically, the US suburb situation came about partially due to racism, and partially due to hostile takeover of transportation infrastructure and PR campaigns by corporations.