Obviously you haven't studied for an ham radio license in the US.
Part 97.115b allows a third party to use a ham radio as long as a
licensed control operator supervises. An legal scenario under FCC rules
would be where the driver is using the radio and the passenger is a
licensed amateur.
And when a ham radio operator (who has no better ability to drive than
anyone else) goes over the cliff because he/she was distracted by operating
his ham gear while driving, at least he wilol know, in those few seconds
before he dies, that he was well within the law.
Private ambulances?
Taxi cabs?
How about that girl that they headlined on, "60 Minutes" that can drive
without any arms....She uses her feet for everything... I guess she would
be legal using her cell phone while driving. Right? Cause she does
everything, "hands free".