The Simpsons and Twin Peaks premièred a few months apart from each other in 1989/1990, and at the time, it felt like a real sea change had taken place in the culture. That feeling dispersed becauseTwin Peaks imploded in its second season, and instead of a bunch of brilliant network shows, what we got in their immediate wake was a shitload of forgotten animated shows whipped up by hacks and Cop Rock. But one thing that both those shows had that really shook things up was a critical, self-aware attitude about TV. Earlier shows that tried for something halfway similar turned spoofy and paper-thin, like It’s Garry Shandling’s Show, a sometimes moderately diverting late-’80s show that, at the time, impressed some critics who’d just learned to type the word “post-modern,” and that, in retrospect, was barely a pimple on the ass of Shandling’s later The Larry Sanders Show. But The Simpsons and Twin Peaks actually managed to make shared jokes based on the fact that smart viewers who’d grown up watching TV understood the basic mechanics of how the shows worked, while still getting the viewers involved in the characters and the stories.
Phil Dyess-Nugent, The A.V. Club