Dont confuse your love of warcraft with a technically unsound film. Just like with BvS having a modicum of fun, getting several lore nods and all the symbolism in the world doesn't make up for lack of basic movie making skills and storytelling. Movie studios are banking on franchise loyalty to outweigh any sort of competency, effort, and risk taking that should be in the film.
That being said The Domestic realease date is the only legitimate time to argue/discuss this everything else is hyperbole.
The raw data from Rotten tomatoes is harsh because people are watching these films objectively, not as fans but as regular people.