I do not believe that Rubey is correct in sying that myths are historical. A myth to me is a made up story that is completely fictional. Take Star Wars for example, all the creatures and the vehicles and weapons in the movie are all pieces of George Lucas' imagination. Only the humans in the movie are real.
Myths are just stories that someone made up at some point in time.
The stories themselves become a part of history, but they are not compiled from historical events. Therefore, I personally believe that Rubey is wrong and that myths are indeed eternal.