Simple math, really.
The
Simpsons minus the genius-ness that the Simpsons series has equals an overrated TV show for people who find irrelevant and random clips humorous (aka Family Guy).
Some people may think that South Park was being "random" with the manatees on the Cartoon Wars episode, but unlike Family Guy, this idea was a great use of metaphor of how it seems as if the writing staff of Family Guy just take random ideas ("idea balls") and put them together to form a "Remember the time when..." joke.
The only way I`ll ever credit Family Guy as "genius" is if the whole reason of creating Family Guy were to make
easy money by
targeting the not-as-mentally-or-emotionally-intelligent group of America (which appears to be a lot) with cheap jokes.