Something major happens in the post-game narrative that recontextualizes the entire story? Oh man, so happy that in six months they'll release a DLC that fixes the terrible narrative decisions, lol. Probably unreliable narrators based on Miller Ross' comments about the whole thing, which sounds pretty dumb too but oh well. I could be wrong.
Rocksteady previously had cutscenes where Barbara kills herself, Joker is the Arkham Knight and Batman destroys Gotham, so who really knows. The general plot is still accurate though, so all the things we hate do happen. You kill Green Lantern, Flash, Batman and Superman, the last of which defeats Wonder Woman.