I work at an ewaste recycling company. Last week, I was testing a projector, and was using a USBC to DVI cable (one of the most cursed cables I've come across). I said "LOL this won't work" and plugged it into my phone. Sure enough, my phone recognized that a display was connected, and once confirmed, showed what I expected it to!
Plugging a car into a phone should work like that: just a dumb display with maybe a keyboard or touchscreen input device.