It's true that Etymology (the source of the word) is neither Definition (a documented meaning of the word) nor Usage (how most people use a word). Your example of dinosaur is fair for showing this, nobody from the outset conceived of the Dinosaur as really just being a "terrible lizard" (this makes me imagine a very lazy gecko, can't be bothered to actually do much "You are a terrible lizard").

BUT telephones really are about voice communications at a distance and not about the particular mechanics that were popularized with the public telephone network. Telephone "numbers", dialling, all that stuff was added later and isn't part of the telephone concept. So although the Latin etymology isn't why these were telephones, they were anyway.