This frustrates me to no end in our family car. Even if I "turn it off", which turns off the radio, the screen still shows a clock over a globe and still glows. There is no escaping it.

Hard to read in direct sunlight, too. (Partially-)Reflective displays with perfect dailight readability exist (used in aircraft), but they would likely not satisfy the cheaper-than-buttons requirement.

But cars without roofs are getting out of fashion anyway. Next step after no steering-wheel will be no windows.