Mythic are an american company. Xena was made by americans. In Xena, the Trojan Wars took place at the same time as Julius Caesar's reign. Why the hell would DAoC be remotely historically, or even mythologically accurate?
Because Atlantis is cool, and this is a game - so they don't need to be historically accurate. Besides, if i were you i'd be more worried about this 'magic' who-har, thats been in the game for yonks and i don't see anyone questioning its historical accuracy.
Or maybe its just that where i live, maybe in other parts of the world people can form magical bolts of fire and burn holes in each other