We all know about the Joker's way of thinking and his philosophy. he's Intelligent, Nihilistic and with a Wicked Sense of Humor. and his views on society speaks large about his character, and i belive so as many of you do that if we add this line in the movie it'll make it significantly better and will show more depth in the twisted mind of the Joker.

what i have in mind is a scene where the Joker sees a kid in a resturant playing Fortnite on his phone while his grandfather is reading a book (insert book title here). and he looks at them and says "damn, we live in a society". he may say this line as he looks into the camera thus breaking the 4th wall.