Ashful
Minister of Fire
I design radio components for a living. MSEE with a specialty in RF electronics. I can tell you they do take up space, and they do have cost, however small. What you call evidence is a misunderstanding, and the fact that Ford had the electronics already integrated does not mean the components have zero cost and size.Sorry to tell you but adding back the AM radio does not take up any additional space - as demonstrated by the fact that Ford kept the components in there all along and just re-enabled them by a software update.
We often leave a function integrated, because the cost of subtracting it from the current generation of hardware may be greater than the cost of just leaving it there. But that does not mean they take up no space and have zero cost, or that they might not be deleted to reclaim both on a subsequent hardware generation. When you're laying out a board which will see millions of units of production, decisions on function groups often go beyond the factors of direct cost and space, such as the NRE and logistical costs of adding it back, if they knew this was a potential item for legislation.