Lady Gaga and Joaquin Phoenix in “Joker 2.” ©Warner Bros/Courtesy Everett Collection “And I think to be an artist, you have to be willing for people to sometimes not like it,” she explained.

Lady Gaga made her acting career the center of the jokes in her Saturday Night Live monologue — roasting her own movie, “Joker 2,” which flopped historically hard in theaters last fall.