Chuck Klosterman said this quote

“ F. Scott Fitzgerald believed inserting exclamation points was the literary equivalent of an author laughing at his own jokes, but that's not the case in the modern age; now, the exclamation point signifies creative confusion. All it illustrates is that even the writer can't tell if what they're creating is supposed to be meaningful, frivolous, or cruel. It's an attempt to insert humor where none exists, on the off chance that a potential reader will only be pleased if they suspect they're being entertained. Of course, the reader isn't really sure, either. They just want to know when they're supposed to pretend to be amused. ”