It's what we had before the laws prohibiting direct-to-consumer/manufacturer-owned dealerships. It's hard for me to find any reliable sources that explain why we got those laws though (was it because direct-to-consumer was bad?)
It seems like the EU has reined in the worst excesses of dealerships a lot, and allows direct-to-consumer. Maybe the US will follow suit in a few decades.
In the early days of the automobile, auto manufacturers didn't have the resources to have stores in every town in America. People couldn't just get a vehicle in Atlanta from Detroit if they didn't have a way to get there. Dealers both organically popped up, and some manufacturers actively engaged with local dealers to get their cars out to a broader audience (e.g. Ford with the Model T).
But as those manufacturers and dealers grew, they then had the resources to operate at broader geographies, and dealers lobbed for franchise laws to "protect local businesses", etc.
Dealerships came about because car manufacturers were demanding that all service go through their dealerships at crazy marked up prices. So dealerships started as way to "protect the consumer" but quickly because terrible places all on their own.
It seems like the EU has reined in the worst excesses of dealerships a lot, and allows direct-to-consumer. Maybe the US will follow suit in a few decades.