People I normally respect have bought in on some crazy-ass conspiracy theories.  Elon, Balaji, PMarca... all super smart, and all tweeting crazy shit. I did some research to see why people get hooked on conspiracy theories:
https://www.charterless.com/p/do-your-own-research-the-psychology

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Examples of crazy conspiracy theories (minus Elon)?

I prefer to just call them theories. Conspiracy is such a dismissive way of phrasing it. Not a fan of the label and removes important discussion and nuance.

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I have a problem with the justification for violence. As for the rest, let’s hear the theory and the evidence. It’s worth hearing because even if it’s wrong, we can have a dialogue and learn why it was wrong. Conspiracy I feel like has become a way to say we don’t need to have a dialogue about this. Similar to 

There are plenty of theories that fall in this grey area and shouldn't be treated that way (e.g. lab leak).  There are others that point to small groups of others (usually of a different race) manipulating events for their own gain and used to justify violence.

For those, it's hard to come up with another approp term.