Re: No distractions please, we're Australian
It depends on the operator of the vehicle, the type of vehicle and what's happening, but I'm somewhat in agreeance with that rule.
After this morning having someone not paying attention and remaining stopped long after some traffic lights went green. Sadly my bicycle lacks a decent (or any) horn — something I'll have to remedy one day.
As for me: I avoid using my radio when I'm in traffic or traveling at speeds in excess of 40km/hr, and would never use a phone. Why a radio over a phone? Once the radio's on a frequency (which I set before departing), the only distraction over a conversation with another person is toggling the push to talk.
Sure phones are full-duplex, thus don't require a PTT, but establishing a call, whether it be an incoming or outgoing call, is generally much more fiddly and distracting. Auto-answer helps, but even then, I'd think twice before using such a thing in heavy traffic.
IMO, wait until you're away from other cars and travelling at 40km/hr or less before fiddling with such a device. As for touchscreen dashboards, I think that's asking for trouble. More points of failure, more fragile, less tactile, not a good option for operating a vehicle.