Conspiracy theories are appealing to people with less nuanced understandings of the world around them.
QAnon and other Blood Libel type conspiracies appeal to those confused by the world around them, those who reject conventional narratives for one reason or another, and those who suffer from black-and-white thinking. Another element is the appeal of being different from the mainstream. It is an easy way to convince yourself you're a free thinker and everyone else is a sheep if your worldview is based on the idea that there is a grand lie or scheme that only you and a select few have noticed.
Also: antisemitism--conscious or unconscious--plays a part in just about any conspiracy theory. If there's supposedly a shadowy cabal controlling society, chances are Europeans are going to assume it's the Jews doing it. As they have for thousands of years.
People latch onto these beliefs for those reasons and find it hard to let them go for numerous reasons. Doing so would take away part of their perceived identity. It would require they admit they were wrong; the more wrong someone is, the harder it is to realize or admit it; the more insane the conspiracy theory, the less likely someone is going to figure out that it is nonsense and the more likely it would be humiliating to own up to being wrong about it. Even if it isn't conscious. Our egos and our need to protect them helps most of us believe lies even if we unconsciously know they are false.
Tldr: People want scapegoats and easy explanations for why the world does not match what their pre-existing beliefs tell them it should be.
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Diagnoses: AS, Depression, General & Social Anxiety
I guess I just wasn't made for these times.
- Brian Wilson
Δυνατὰ δὲ οἱ προύχοντες πράσσουσι καὶ οἱ ἀσθενεῖς ξυγχωροῦσιν.
Those with power do what their power permits, and the weak can only acquiesce.
- Thucydides