Outside of the big volume knob or a big tuning knob, you have to look at small buttons. I can change the climate control, volume, cruise control settings, wipers, track/station, make or receive a phone call, listen to a text message all without taking my hands off the wheel. I change music sources with one button press on the touch screen. Same for the heated seats in winter.
It can't get much simpler than that. What else do you really NEED to do while driving?