Get real.
I don't think South Park ever implied both parties are equally bad. Just that they are both bad. And I don't think irreverent satire is prep work or psy-op propaganda for an authoritarian government. If anything, it's the inoculation.
It's quite clear that you haven't watched the series in the past decade. I'm sure you wouldn't be crowing the same tune if you'd watched the Mr. Garrison storyline.