Let's be honest, all their games have not been as big as WoW ever was.
Not only that, Classic WoW alone shows that the WoW title can still dominate the gaming market.
It is ashame their main devs got moved over to work on other projects, because Blizzard must realize atm how populair their title still can be if they actually tried.
(Still #1 on twitch on a daily basis, which hasn't happened for years if you don't count release date and even that is over after 2-4 days)