It means if you are a crazy person, you can no longer waltz in off your motorcycle and demand all documents related to alien spacecraft held at Area 51 or the real unedited Zapruder film that clearly shows Walt Disney was the triggerman, etc.

My guess is anyone could still pursue whatever crazy theories they wanted, so long as they conducted their research legitimately, i.e., as a legitimate _process_ of research, with no value judgment on the topic or end goal.