There’s no good reason to call Guild Wars 2… well, that. The title of the original Guild Wars already didn’t make a whole lot of sense because the actual game wasn’t about the eponymous Guild Wars; those were over and done with. But Guild Wars 2 features no additional guild wars! It actually features less warring of guilds than the original did! Guilds and the wars thereof are totally irrelevant, and the title makes no sense whatsoever.
If it isn’t obvious from the premise, this is a silly thing to care about. The game is Guild Wars 2 because it’s a sequel to Guild Wars, obviously. But there are a lot of MMOs with titles that are either not particularly descriptive or outright misleading. You only explore one galaxy in Star Wars Galaxies, the presence of a number means that Final Fantasy XIV is obviously not final, and don’t even get me started on how many winter events happen in Neverwinter. So what MMO titles that are somehow non-descriptive or inappropriate bother you more than they probably should?