Part of the issue is that "conspiracy theory" is a pretty broad category. Secret cure for cancer that only Reagan knew about? That's a conspiracy theory. The government spies on its own citizens without a warrant? That was a conspiracy theory until Edward Snowden gave it some authority. Sometimes the whacky stuff turns out to be true. Of course, the difference seems to be that actual evidence and credible testimony seems to follow some of these things but not others. One of my favorite conspiracy theories is anything to do with FEMA camps. FEMA can't get bottled water to a crisis scene but they can plan mass incarceration and genocide, apparently.