> I don't see anything objectively more or less dangerous about operating a radio in this way

In my current vehicle I can change stations without taking my eyes off the road, I don't feel as if I'd be able to do that if it were on a touch screen due to the lack of tactile feedback.

Also, I've rented a few vehicles and I've never seen one that didn't have things like A/C on the touch screen, which is part of why I've formed the opinion I have. OTOH, what I've rented are minivans, where A/C is a bit more complex since it will often have a "driver/passenger" dichotomy as well as a "front/back"dichotomy.