I know, that's a weird question. Let me explain my thoughts. So lets say that Optimus comes down in a protoform and hits earth. He walks up to someone and says, "I am from Cybertron." Anyone would assume that he is from another solar system. But does he know that Jupiter is called Jupiter? No, that's what we named it. What if the planet we called Jupiter was actually Cybertron? It's a strange question, but I have never seen that point raised before.