> IMO burying digital tone controls in multi-level menus in cars is user-hostile and unsafe.

Forget the tone. The other day I was in a Renault Megane with two friends and the radio's F/R balance was out of whack, with the rear speakers, placed near my ears, going full tilt. We had to stop the car and figure how to change this, since the controls were not at all intuitive, including for the car's owner of multiple years.