Maybe, but Cartman has kinda always been portrayed as evil and an ass. He's generally the butt of the joke, not the moral guide of the series.

Kyle and Stan are usually the mouthpieces for Trey and Matt. In the classic formula, Kyle would walk out at the end of the episode and say, "You know, I've learned something..." and then just tell you the moral of the story.

South Park used to be the boogeyman that parents would point to as "ruining kids." I think there's some truth to that. It can ruin your kid if they have absolutely no media literacy and just watch it because they think Cartman's funny (but if they already were on Cartman's side, who ruined who?)

There are plenty of viewers like that (see: the "South Park is woke now" crowd), and Cartman has been pretty much just a piece of shit since day 1.

I'm optimistic about this character arc for Cartman, because they're basically just making it as undeniable as possible that he revels in being a piece of shit. If Cartman sees everyone becoming like him as a bad thing, that will be more effective messaging toward the people that only watch for Cartman.