I agree with your first sentence at least. Conspiracies -- from what led to Jan. 6th to Watergate to John Brown's Raid to the XYZ affair -- absolutely exist. But the word has been so completely conflated with absurd, even insane ideas, that to talk of conspiracy immediately puts the accuser at a serious rhetorical disadvantage.

I use the term "contrarian theory" to describe what is usually meant by "conspiracy theory".

I'm not terrified of having "wrong thoughts", but I do think conspiracy theorizing is dumb because no conspiracy theorist seems able to believe just one conspiracy. Oh, you think COVID was a lab leak, and that global warming is fake? What do you think about the moon landing? Is the government controlled by the Jews or the lizardmen? Why don't you (and this is a purely rhetorical "you") seem to have any limits to your credulity, whatsoever? Surely some things are too outrageous to be a priori likely and require specific evidence!

If you believe everyone who thinks the lab leak is viable also believes in lizard men, I'm not sure what to say.

I don't believe everyone thinks anything, but I've met a hell of a lot of people for whom conspiracy theorizing is a kind of black hole: once they fall in from one direction, they start buying into a variety of theories more fundamentally wacky than the original thing that got them into it.

That seems like a remarkably poor hereustic

How is a prior a heuristic?