The Secret Origin of Denzel Crocker - S3-E8
Factual error: Each time Timmy jumps through time, he goes back 10 years from 2002 (1992, 1982, 1972). However, some of the 80's references, such as Miami Vice, Flashdance & Back To the Future all came out after 1982.
Answer: It's a joke. One cannot list all forms of entertainment. The list would never end. The boys were trying to convey how superior they were to the others, by saying that they were too good for comedy.