At least there are some good guys among the bad and a bad guy among the good; so it adds some drama.
Tell me what action/fantasy/sci-fi movie is not good guy vs. bad guy ? More specifically, bad guys have an evil plan to do something destructive, and good guys somehow ruins it. Star War, X men, all the superheros ones, 007, and I can keep name more (at least that is the theme of the individual movies, if not the theme of the whole sequence).
The critique Warcraft received most is about the lack of character development; lack of a clear lead actor/actress. In some sense, it is not necessarily a bad thing because it breaks the old "one dude with protagonist aura that never dies" Holywood pattern.