That is the narrative, but it doesn't stand up. Suburbs have existed for over 100 years now, and those older ones have managed to tear out the streetcars (on hindsight a mistake), put in sewer, water, phone, electric, cable tv - most of the above list has been replaced several times. They seem like they must be siphoning from the larger city until you realize that they are not replacing all of that every 20 years and so depreciation is not a clue as to the real long term costs.
There are exurbs where you get acres of land, those are generally surrounded by farms (at least for the first 30 years until the suburbs expand out that far - but then a developer will buy those acres and divide it for more houses) In the suburbs you are looking at more like 10 houses per acre - which is not very dense, but still much denser.
The US has good building codes. There is no place where you can get by with an uninsulated attic - except in the bad parts of big cities where houses from 1880 are still around and not upgraded.
edit: uninsulated attic