[joeysteele]

I don't know really.

I think it desirable to set stops to check your phones.
It is different talking to passengers as they like you, are looking at the road too.

Even though, just walking talking on a phone, your near full attention can be focussed on the call.
So concentration impaired.

I never use any phone while driving.
I stop at selected places to then check my phone and deal with anything urgent.

I see no reason to use a phone except in an emergency when driving.
How on earth did people and businesses manage before, when they didn't exist.

On balance I'd lean to avoiding use of them including hands free.
Banning the hands free too, I'm not sure how that could be properly policed as others have said here.