They already are. Android auto and Apple carplay use your smartphone's brains to display on the car's touchscreen.
I'm curious how much control is offered on these Android Auto systems. Ideally in my mind, there would be protocols for controlling windows, sunroofs, seat controls, HVAC, interior lighting, windshield wipers, defog, maybe even running lights headlights cruise control & those closer to the driving experience aspects. The whole car experience should be BYOD.