I think they’re in a tight spot. With South Park plots, usually there’s a neat bow to tie it all up. And when they do social commentary or political criticism (except for that one bad season), they can just mock whoever it is and go back to normal life at the end. But since the current state of the US is pretty exceptional, and it seems to be in free fall, there is no real way to end political episodes. The people they’re mocking can’t be portrayed to change, grow, die or become irrelevant, so there’s only so much they can do.