How far back do you go? I go back to the 60s and remember the JC Whitney catalogs. In the last 60 years at least you could repair any car with anything. If it was under warranty and you didn't use company parts you voided the warranty, but once that was passed you could repair any car with any part.This argument of 'there is always Andriod' does not wash because back in the day car manufacturers tried that argument and they was hit hard for it. Car manufactureres used to have a monopoly on car parts and repairs, if you wanted a particular car, it had to be repaired by an authourised dealer and spare parts had to come from the car manufacturer.
How do you think people made hot rods in the 40s and 50s?