I don't agree with Scorsese about superhero movies, but I have to admit that this one really helps his case. The individual scenes are all very good, but they don't actually coalesce into any kind of story, only the vague outline of something resembling a plot. It's like a short film anthology. Jack Nicholson plays the same character he always plays. There's a bunch of good music by Prince, which is awesome but doesn't fit the movie in any way.
It was always one of the weaker superhero movies, but it's worse today: Batman and the Joker are totally played out, and their weird creepy fans have destroyed whatever appeal they still have left after so much overexposure.