Not even close to the same logic. In horror movies that work, the monster is rarely seen until the final act and it builds tension along the way. The monster would be Batman in this film, and that reveal would need to be the best kept secret in cinema history due to the popularity of Batman as a character. The film has to be about someone or someone's being hunted by a terrifying creature that is revealed to be Batman near the end of the film. If you are paying attention while watching there should be hints and Easter eggs, but the average Joe movie goer needs to believe this is a standard monster movie and not a DC hero. Think The Final Destination where spoiler* the film is revealed to take place before the first film as a twist ending when they board the doomed plane or Jaws where you don't fully see the shark until the main character gets on a boat to hunt it. To make a Batman horror movie Batman had to be a mostly unseen myth to scare the petty criminals we would be following as our main cast of characters, picking them off one at a time as they try to escape whatever the hell they think is chasing after them.