> and the information is carried via audio?

Because it's not. Facial expressions and body language carry gigantic amounts of information.

So many misunderstandings arise when the channel is audio-only. E.g. if a majority of people in a meeting are uneasy with something, they can see it on each others' faces, realize they're not alone, and bring it up. When it's audio-only, everyone thinks they're the only one with concerns and so maybe it's not worth interrupting what they incorrectly assume to be the general consensus over audio.