In this special, South Park makes several statements about modern social trends, and they are all 100% accurate.
It draws attention to how horrible and hypocritical big pharma is, and also evilness of corporations that feed off the unhealthy lifestyle of middle, mid/low, and low class tiers. It also focuses on the plight of the average unhealthy American, and how it IS a choice for many to be overweight, but also how difficult it is to choose a healthier lifestyle. It teaches us acceptance, while farting in the face of social predator morons like Lizzo.
And the jokes are fantastic. There are blatant jokes, and sort of subtle jokes. I especially loved the random 1-sec long doo-wop singing of the classic "Golden Crisps" theme. It's a small, yet blaring piece of evidence that the brains of South Park still got it.
And let us not forget the CLASSIC and typical story arc and motivation of Cartman's character. It's on point, never-changing, and it's one of those episodes where he either gets his just desserts, or it ends with him winning and everyone else frustrated. Either way, it's a win for the audience, especially those of use who have been with the show for eons.
Only a few minor drawbacks to this special. For one, there are a few moments when it seems like they're either phoning it in, or trying too hard to be "typical South Park" (case in point, the side effect of "Lizzo" with the ears). But then again, maybe that's what makes South Park so "South Park" and they're merely sticking to the original recipe of the show.