I mean if we can't agree that Joker making over a billion is a pretty concrete example of the character's draw then there's not much left to talk about.
I suppose in a parallel dimension there's a relentlessly grim, action-scene-free movie about a depressed Joaquin Phoenix dressing up a random kids clown with no Joker iconography making that kind of money but, I'm gonne be honest, I can't see it.