I love South Park. It's irreverent, politically incorrect, it pokes fun at everyone indiscriminately. No one is safe from their black humour ... even their own voices! Hayes left because they poked fun at Scientology ... I mean geez, like that cradle of madness could escape the arrows of SP wit.
I love that show. I think it's the perfect antidote to a world overwhelmed with PC madness. Ya, Irwin was awesome (if a tad insane) and a man who did a lot of good, but there is simply no immunity from dark satire. The best and the worst of mankind are equally likely to come under the South Park writers' guns. More power to em ... I don't think it would be easy to write this kind of show without showing any favouritism but they manage. Everyone gets whopped with the SP satire stick.
I suspect Irwin, wherever he is, is laughing his butt off at this. He loved attention and I seriously doubt he'd have worried about something like this.