There are a lot of words that are associated with the high praise of South Park.
None of them are really accurate.
The fact is that Trey Parker and Matt Stone are jerks. They really are, there is no better word for them. However, they are hysterical jerks.
It's not satire and it's not social commentary. What you are doing is watching Parker and Stone ruthlessly mock people. Just because the cruel mockery is witty and intelligent doesn't make it any better.
However...it is witty and intelligent, and it is hysterical...so even though it gives you the feeling that you are laughing with the school yard bully, you're still laughing.
And you are still laughing because it is funny.
The celebrity takedowns are world famous and the shows ability to hold a mirror up to society in a fun and entertaining way seems timeless.