The speaker was a psychology researcher from UK who flew here for that, and the talk was about conspiracy theories. When they introduced her they stated that she wouldn't accept any questions from the audience.
This was received with boos and shouts that it was not real science.
She then proceeded to bundle all the conspiracy theories together. Going from "the government is doing something bad" to "earth is flat".
After that talk I can really believe that the bullshit conspiracy theories are made up and spread artificially so that anyone that comes up with any conspiracy theory can be shushed as a crazy person.
But… in reality conspiracies do exist. One can make a theory and then test if it's true (or get killed/imprisoned by the government while trying).