I've personally never seen an interview with single "white supremacist", not even a fake one. I think they're petrified that someone they're trying to label "white supremacist" may say something that makes sense, if given a chance to speak freely on his views.

Going back about three decades, some may remember "Daniel the KKK Guy" from the Howard Stern Show. On one episode, they were trying to actually get at his psychology, for why he didn't like black people. Daniel finally said, "Oh no, I don't dislike black people. I just like white people."

Going by today's standard, though, such admission may be deserving of summary execution.