Thing is, there really isn't that much differentiation between automobile models. Everything out there is basically a sedan, SUV, or pickup truck (even the Jeep

Thing is, there really isn't that much differentiation between automobile models. Everything out there is basically a sedan, SUV, or pickup truck (even the Jeep Wrangler is being forced, kicking & screaming, into the SUV form) with little meaningful difference between variants. In "trying as hard as possible to horizontally differentiate from the competition and vertically differentiate to access more segments", manufacturers are trying really hard to make car-making as hard & difficult & expensive as possible. So back to basics: it's not that hard, it's a well-understood process with a robust supply chain ... an industry ripe for one company to arise focusing on turning designs into vehicles, without the additional overhead of design & marketing. Insofar as the "flow shop" for car manufacturing "would take an order of magnitude or more investment", well, we all know one company that does have that kind of cash (!) lying around, and the interest in re-inventing the automotive industry.