Conspiracy theories are like witch hunt.
Once one believes a conspiracy is true, there's nothing that can make him believe otherwise.
"But look! She doesn't look like a witch. Does she?"
"That convinces me more that she is a witch. Witches can shape shift to look pretty."
"But don't you feel sympathetic looking at her tortures?"
"That's because she is throwing spells to create sympathy towards her."
Next look around in our community and see how many conspiracy theories you find floating around. People so much obsessed in believing in those. The more you argue with them the stronger their believes get.
First they sound cute, harmless, a bit stupid. But cutely stupid.
But that grows. Until they end up harming others for their believe. That doesn't happen overnight, but just give it some time.