It's not an assumption I've really examined before, but why do we have names?
Names are just a string of characters that may or may not have a literal meaning in some language. Sure, names used to convey information such as personality attributes or occupation, but that time is long past. The only thing names seem to convey these days is a general indication of your ethnic heritage. Even their primary purpose as a unique identifier of a person is slowly losing effectiveness; I know of another person with my exact first and last name that lives within 100 miles of me, and both my names are uncommon to rare.
My primary conclusion is that we have names precisely because we cannot vocalize mental images of faces. However, computer networks are making it extraordinarily easy to broadcast images these days, and even live videos. Will this make our textual names less important?My guess is no. Rather, as the world reaches into 10s of billions of people, every opportunity to distinguish ourselves from eachother will be needed.
It seems certain that our individual identities, whether in a face or a name, will continue to shrink in importance next to abstract concepts and large organizations. Yet, it is through our relationships with other individuals that we build our identities and derive meaning.