So much of what we say is for comfort, not content.
Some friends of mine have a baby that is now about 3 months old. He recognizes the voices of his mother and father and clearly takes comfort in their sound. But that is all their voices are to him, comforting sounds. He cannot understand what they are saying, but just hearing them is reassurance that he is safe and loved.
I don't think we ever lose this need for comforting sound. Other people's voices and noise generated by our environments, seems to reassure many of us that we are not alone. In the past, i've had people call and say, "I just needed to hear your voice." I've yet to be contacted by someone who's said, "I just needed to receive a text from you."