During my internship on automotive cost engineering, I quickly learned that motorized anything on a car costs and weighs leagues more than its mechanical-only c

During my internship on automotive cost engineering, I quickly learned that motorized anything on a car costs and weighs leagues more than its mechanical-only cousin. I am curious why Model 3 went down the path of total motorization, when it is marketed as a more affordable car. Would it be more costly or less costly for Tesla to have just one set of underlying mechanisms for all of their cars at all luxury levels, or have different sets of mechanisms depending on luxury level? The motorized mechanism could be adapted to all levels of luxury by simply changing the controls.