I mean imagined conspiracies never come up with anything solid. When you ask where's the evidence it comes in very thin. Conspiracies do exist and they only remain concealed if there's a very small number of people involved and they're very good at covering their tracks. Even then they tend to be outed by investigations and documents years later.
911 truthers, the election steal, Q anon, pizzagate. All very very thin on substance given the broadness of the alleged cover ups and the low quality of the facts surfaced.