Bowden said that her team consisted of the odd conglomeration of people that were drawn to overnight work looking at weird and disturbing stuff. “I had a witch, a vampire, a white supremacist, and some regular day-to-day people. I had all these different categories,” Bowden, who is black, said. “We were saying, ‘Based on your experience in white-supremacist land, is this white-supremacist material?’” That right there…
Could you really trust the white supremacist to correctly ID the material, though?
The same goes for pornography. There's a lot of weird porn which gets away with being on sites like YouTube because it's too esoteric to be recognizable by most reviewers. For example [NSFW but not explicit]: https://www.youtube.com/watch?v=BWW8_8fc0-E -- there isn't any exposed genitals or sexual activity in the video, but it's clearly made to arouse people with the right fetish. (Just look at the comments if it isn't obvious.) A reviewer who's familiar with "weird porn" would likely be much better at recognizing fetish material, even if it's a fetish they don't personally enjoy.