Also in today's world it is cheaper for one machine to produce 1.000 identical parts than for the same machine produce 10 times 100 different parts. You need stock of each, tests of each.
Imagine how efficient car maintenance would be of only we'd use one standardized car. You can have the larger model, but all components are the same, every garage has them...
Like Tesla is doing with one engine for all cars and a mono frame pressed out of a metal sheet. Cybertruck deliverable in every color you like as long as it's metal. I have read somewhere the complexity in production lines are similar as the big O notation. Henry Ford would be proud of Elon.
Most car manufacturers are massively reducing complexity. Toyota's Next Generation Architecture is reducing total manufacturing costs by 20% by simplifying their entire platform of vehicles into a common set of types and using similar hardware wherever possible.
Imagine how efficient car maintenance would be of only we'd use one standardized car. You can have the larger model, but all components are the same, every garage has them...