I feel like you're deliberately missing the point.
You don't need them to have a reversing camera. Literally millions of cars over the past 2 decades have perfectly fine reversing cameras using the screen of a regular double-DIN deck (or fold out single-DIN deck).
I, too, felt you were being intentionally dense in this thread. We've just been talking past each other.
I don't see a meaningful distinction between a screen on a DIN unit and an integrated screen.
With Android Auto or the ios equivalent -- a hard requirement for most car buyers today -- a touchscreen is basically required.
Other "smart" features aren't required but I'm not surprised car companies want to try and extract value from in-car tech. It's got nothing to do with providing value to consumers.