When Daewoo entered the UK market they made a big deal about not having franchise dealerships or commissioned salespeople. After a few years, the Daewoo owned showrooms were replaced with traditional dealerships.
Companies outside of traditional franchises haven’t cropped up selling brand new cars. New car sales happen through dealerships. Online sales, through specialists like jamjar.com, never took off.
None of this says franchised dealerships are perfect nor that they’re the same between the UK and US. However, in a place without restrictions on who sells new cars there has been no significant change in the model.
Also, FWIW, Daewoo is basically a non-entity in the US auto market. I'm not sure how they fared in the UK and EU, but if it's similar, that may be a confounding factor with that particular answer. And, generally, I think the dealership model arose originally because the auto industry is immensely capital intensive before you start talking about having inventory sitting on a lot in every minor city in the world. And the auto industry was more speculative, so the manufacturers were happy to let someone else front the capital for carrying finished inventory. But the auto industry is established and capital is plentiful these days.