So you’ve added the criteria per capita; I still think you’d find that the gang milieus that gangsta rap (in its various forms) is closely associated with vastly overshadows any isolated cases of Nödtveidt or Varg-wannabes there still might be out there. Black Metal is also one of the most popular subgenres of metal nowadays, so the per capita argument doesn’t really apply.

RAC/White Power-music perhaps, but then only because the fanbase of this music is so embarrassingly small.