But there are (somewhat) wise individuals who have not yet thought carefully about existential risk. They're forced to heuristically decide whether or not thinking about it more makes sense. Given what they know at present, it may be rational for them to dismiss Eliezer as being like a very smart version of the UFO conspiracy theorists or something like that. Because of the halo effect issue that Yvain talks about, this may lower their willingness to consider existential risk at all.