Kind of foreshadowed in 5th Element when the Chinese Junk restaurant is serving food to Corbin Dallas at the window in his apartment.
They illustrate it with a picture of a high rise tower. I always thought that in a world of flying cars, people wouldn't try to live in very dense city centers but rather would live in a spacious house with a garden far away as it only takes a 15 min commute to fly 50km at 200km/h. Flying cars pretty much eliminate traffic jams.