If you are dominant or want to become dominant you do not want to be swayed by the words of others. So ideas are less likely to be dangerous to you or your values. If you are less-dominant you may be more susceptible to the ideas that are floating around in society as, evolutionarily, you would want to be part of whatever movement is forming so you are part of the ingroup.

Another possibility is that we are seeing some other personality differences in openness and or agreeableness. People who are higher in openness and/or lower in agreeableness might be more interested in ideas that are judged politically incorrect, or antisocial.