Absolutely. Any distraction can be a recipe for disaster. When in communication on phone ones attention is diverted to the conversation...awareness and brain reaction to moving surroundings becomes compromised. Save your communications via phone for when you park it.
Don't misinterpret me here...I am not suggesting that drivers should be mute and not converse with passengers. Its that phone and mechanisms that are problematic. New vehicles have options to talk via phone hands off. Provided the conversation isn't emotionally charged or require serious brain concentration, go for it.