I don't see how that's opposite. Not believing in conspiracy theories doesn't imply not thinking critically. In fact, critical thinking is pretty harmful to most conspiracy theories.
Correct, but some people are rejecting every conspiracy theory on the sole ground that it assumes conspiracy, and this heuristic is not critical thinking.
Given the amount of signal vs noise, I think it's pretty reasonable to ignore the crazies until they can back up their claims with hard evidence.
If they can't do that, their "theory" isn't worth my time. Now if one of the crazies keeps bugging me with his theory, I might apply critical thinking to shut him up, if I don't lose patience and punch him in the face first.
You've just contradicted yourself. On the one hand you state critical thinking is key and on the other hand you dismiss questioning popular opinion as crazy.
Conspiracy theories are not "questioning popular opinion". You can question popular opinion without coming up with crazy theories, or at least, you should take them as what they are: wild guesses at what might explain some discrepancies in that popular opinion.
Conspiracy theorists usually show a strong belief in something pretty improbable without a shred of tangible evidence. I think it's fair to label them as "crazies" because they tend to be very vocal about it and impervious to logical flaws in their own theories. And they're annoying, when you annoy people, you can expect some kind of negative feedback, like being mocked or called names.
