The point is that Blizzard did this expansion because Azeroth has mostly been explored (minus Azshara and the last two old gods) and the world of Draenor was destroyed in lore and they wanted to restore Draenor so we could explore it and the other continents. We could have went to Argus too, but Draenor has orc lore, ogre lore, draenei lore, arrakoa lore, and is kind of a more significant planet with room to expand upon while Argus seems to be just demons and the old draenei home and a lot of new lore will have to be made to develop that planet. It is "technically" time travel but the premise is that we have a new planet to explore and Blizzard is making it as little about time travel as possible. But you just want to say it is "time travel" in the same way Chrono Trigger has time travel, so you can flame blizzard for not being as good at it when their intention was to restore an old planet they regret destroying in lore after how successfully and long lived WoW has been.