He also played a version of himself from another reality in Rick and Morty, which Dan Harmon later deeply regretted portraying him as a genius. Although that could be explained by the fact that it's an alternate universe version of him where he's not a fascist prick.

Lots of people fell for his veneer of competency and glazed him like crazy in those days, and there was a real groupthink mentality behind his supposed genius - he was always portrayed by the media as intelligent and then when people hear about him in passing for the first time they come to a conclusion that if that many people think he's a genius then he simply must be.