STUPIDITY ONLY PARTLY EXPLAINS HOMOPHOBIA
People with low cognitive abilities are significantly more likely to demonstrate homophobic prejudice.
People with low intelligence prefer the security of an authority who tells them what to think rather than to take the risk of forming, and expressing, their own opinions in a world that might judge them for having an alternative point of view.
Since right wing conservative ideologies are more authoritarian, that set of beliefs attracts people who are not very smart. And since those same ideologies promote a dislike of others who are outside of their immediate group – people of different races or sexual orientations for example – those are the ideologies more frequently adopted by people with poor cognitive abilities.