I agree many manufacturers have gone a bit overboard in making even things like vent positions and glove boxes behind touchscreens. But at the same time, I don't want touch screen to completely disappear. Punching in a destination and controlling the navigation interface is way better with a touchscreen than using a dial. As a passenger or while stopped, changing the media with a touchscreen interface is better than a dial. Changing a lot of the finer settings in the car (ones you wouldn't be doing while driving) with a touchscreen is better than scrolling through menus with a dial. For the most part, a lot of things you'd do with the system while not moving or while being the passenger can be better on the screen than with a bunch of physical controls, controls which would necessitate making the screen a lot smaller.

Also, then when wanting to quickly reference the navigation system, having a larger screen with larger items on it means it is easier to understand what it is telling the driver in a glance. Having a ton of physical controls means it is a much smaller map, meaning smaller items on the map, meaning harder to understand at a quick glance. It's nice having the next turn up in the driver's information cluster or on a heads-up display as well to reduce the needs for the driver to reference the larger navigation system.

There definitely needs to be a balance of physical controls versus software buttons, but I wouldn't buy a new car without a screen these days.