Only because they are the only thing that most zoning codes in the U.S permit to build. With U.S zoning being what it is, there's literally no honest discussion to be made on what type of housing is most economically viable.
So if we go back to smaller places it’s viable. The only reason it’s not viable in places like Europe is because there are so many people in a small space. In the USA we could get adequate population density with 1200 sq foot homes and 1/8 acre plots.
My father managed several factories in the LA area. Upgrading the electrical for new equipment in the close to downtown factory was going to cost something like a 6 to 7 figure sum. The factory in the boondocks upgrade was a quarter of the price.
A suburban neighborhood that hosts a few dozens of families requires more infrastructure, but can be replaced by a single 10 to 20-story building. An large apartment complex can serve hundreds of families.
Now, it doesn't have to be a dichotomy. It should be even more cost effective to build tall apartment buildings in the suburbs near the city. City-nations tend to expand capacity by creating new towns in suburban areas and extensive planning. That's much more efficient than US-style suburban sprawl.