If they did it about teeth it would still be a nod to the trans culture war. Again, that's the point - it's current event satire. The show is two guys mocking everyone in the context of a current moment in time. Early show didn't necessarily start that way but it's developed into that because they got tired of coming up with episode ideas about random things and just started taking inspiration from current events.

You don't have to like it, it's not for everyone. But if you know people who take any of the "messaging" seriously and don't agree with their views that reflects a lot more on those people just being dumb than it does the content of the show.

Anyone can get whatever they want out of any piece of media, but the POINT of South Park is satire. Offensive, outrageous satire. If people get offended or take anything seriously then they're part of the show's zeitgeist. This isn't just my interpretation, it's communicated clearly from the creators over decades of their own speech on the subject.