I find that there is still something to learn from the guests that are batshit crazy.

You learn what aspects of their message resonates with their audience, even if their reasoning is clearly flawed. Rogan is unique in that he frequently let's guests speak freely enough that they divulge the reasons they believe the things they do. And that insight can be incredibly enlightening.

As Aristotle said "It is the mark of an educated mind to be able to entertain a thought without accepting it."