And my point is that in making of fun all shades of the political spectrum, they're essentially putting down anyone who makes a stand which, in turn, inadvertently becomes advocacy for the status quo.
'Anyone who makes a stand' is a huge exaggeration. They target the extremes. South Park was/is progressive on race equality, gay marriage, foreign intervention, etc. What they mock is the extremes (PC principal, gun nuts, racists, Scientology, and so on).
As an example, the latest episode wasn't mocking African American athletes for sitting out the national anthem. It was mocking the media who sex it up and use it as a selling-point.