I've seen a lot of fans comment on how helpful this episode was, how it exposed those fake "transtrenders" for who they are and--yeah, that's just the problem. Trans people aren't just "fake" men or women anymore to the cis folks--nah, now they're fake...trans people?
I get Cartman wasn't "really" trans and just wanted an excuse to use a nicer bathroom (specifically, the girls'), and the idea of the episode was that people shouldn't use the struggles of others as means of granting special privileges. But that just puts forth another..hell, several harmful myths about trans folk.
That we need to pass some kind of "Are you struggling enough?" test in order to "pass" as being "truly" trans (you knows, as if trans folk don't get enough shit for trying to pass as their own gender as is.)
That we're making this shit about being hurt by cis folk up. That we're all just a bunch of whining Cartmans, complaining about nothing.
In the case of transwomen, that they're not really "women" at all, but simply men who want to use a nicer bathroom. Gotta add more fuel to the "deceptive transwoman" myth fire, apparently.
Yeah, yeah, I know. Matt and Trey are out to offend everyone, South Park is out to offend everyone, trust me, I used to be one of those South Park fans, I've been there. I get it.
But the thing is, it's not just out to offend anyone anymore. It's been making statements for a long, long time now, and they're really influential statements, especially for young audiences (young enough that they shouldn't be watching the show to begin with, but I think people are past the point of caring about South Park's age demographic). Some of these are good statements, like Butters's speech in the "Cartman Sucks" episode. Others are downright dangerous, like arguing it's fine for people to use the word "fag."
And the young demographic really fucking loves latching on to those dangerous ones in particular. Especially if it's about a topic that gets little (if not any) coverage in the media--like trans issues.
I think you see where I'm going with this.
The episode wasn't completely without merit, there seemed to be an attempt at sending a genuine message about self-expression across with the Lorde subplot, but kids aren't going to remember that. They're going to remember Cartman claiming to be transgender so he can use a nicer bathroom.