not USanian but afaik cars got so big over there because trucks (being work vehicles) have less (environmental, safety, …) regulations than cars, that’s why SUVs got so popular, manufacturers pushed them onto public. as long as the base for the vehicle is that of a truck they are legally exempt from many limits.

source: probably “Not Just Bikes” on y*utube idk

EDIT: just read about the chicken tax, interesting…