I don't see why it isn't obtainable anymore, probably just a GM who doesn't know what he is saying.
If people could remember back, Blizzard said only METAS would be account wide progress --> Hero of Shattrath will require completion on ONE charecter.
As a person who completed it, I'm completely fine with it being obtainable, however you have to do the grind on one char. The "hard" part is getting from hated to neutral..