That "far future date" answer is just a version of "no."

It makes no sense to tack a 2 onto one of the best brand names in gaming. If they decided to make a major engine update or paradigm shift, they'd roll it out progressively via expansions, which themselves over time have always included evolutions and improvements.

In effect, most of the major expansions in WoW have been sequels to WoW. It has never been necessary to label them as entirely new games.