First cartoons were for adults. Betty Bop was a risque wonton woman, most of warner brothers cartoons were considered subversive and some are were banned and still can not be shown even today. Than came Fritz the cat, the original x-rated cartoon. When I was a kid my parents went to see it and that was my goal was to see this movie finally did years later not as out there as I had thought, Heavy metal was way more sexy.
Some of the new ones on TV our just social comentaries and can be real funny but they are trying for the OMG factor way to hard. It should come naturally from the charaters and stroyline. This is what makes the Simpson the longest running adult cartoon ever.