It is not only in America. The same happens everywhere.
For decades a car has been a symbol of success in life. Many people could not afford it. They felt inadequate and envious becase of it.
Nowadays more people can afford the car. So that is what they do. They buy and drive cars.
The situation will get worse, when the Chinese will start buying cars en masse. This process has began already. This will be the end of Earth as we know it.
The car with the combustion engine is very malicious contraption. If you switch on the combustion engine in a closed room, a garage for example, you will be dead in minutes. On a calm day, when air is not moving practically, we have to breath on a busy street the exhaust almost as if we were sitting in such a garage.
Most of us do not need a car at all. Commuting by cycling or walking is much more fun. Being carfree is also liberating from hypodynamia, constant worries, sheikhs, etc.
For people, who are really lazy, there is also the better alternative.
It is the car powered by the compressed air.
Ironically, Henry Thoreau lived also in the USA. His work and views make a lot of sense, especially now, when we see to what end it all came.