[Maru]

Family guy took off around the time the Simpsons were introducing more radical/parodistic changes to the model. So it never took itself seriously at all. The same can be said about South Park. Though South Park was in that "cool" medium-rare zone of US cartoons that was on the fringes at the time. Where it wasn't quite vulgar enough that it was Beavis&Butthead-y (which was cancelled at the time), but still vulgar enough to appeal to the older Millenials. US shows are becoming less censorship-heavy, so there's not really a niche for vulgar/outrageous anymore. It used to be if a show was not "family-friendly" enough, it was petitioned until it was pulled off the air in the States. Now that pull is in the other direction... how dare it not break norms, etc...