Earlier quoted context omitted.
Care to elaborate on your reasoning? The people playing on Nostalrius aren't suddenly going to switch to the latest expansion, so there's literally zero incentive for them to go after it.
It's exactly main reason: Blizzard have right to control the history and evolution of the WoW universe. Players can still play on old locations even on official servers, but things like game balance, economics - it's all was made by Blizzard and they have right to change it, for good or bad.
That is not true, unfortunately.