One still needs to look at the screen but it is a momentary glance to see we've landed on the right menu. And often with systems like iDrive or Audi's MMI, the screen is higher up near the level of the road vision. With a touchscreen, you have to stare down multiple seconds at your finger while you punch in commands or an address. Plus, you have to reach forward.......
I know with iDrive they've had handwriting possible on the puck for a few years now. So it's even easier to input without constantly looking down.
Of course, it's everyone's personal preferences. I have to deal with a touchscreen and almost no buttons on my Peugeot- the only hard buttons are the central locking, defrost front, rear, hazard, and air recirculate. Often I *miss* when I punch climate or radio or navi and have to look down again. I've learned to deal with it. But a rotary + screen menu setup is easier to manipulate in my books.