Unz Review is an absolute garbage heap, but Unz is able to maintain some plausible deniability because UR did host some genuinely good leftwing authors at some point, like Juan Cole and the late Alexander Cockburn.
Still, he also provides the primary platform for “race realism” content. You mentioned Sailer. There’s also Anatoly Karlin and James Thompson, who tries to present the case in a more moderate nominally dispassionate way. UR includes a few opponents to race realism, too, like Chanda Chisala.
I didn’t know about his Holocaust denial though. I had always assumed he was just a libertarian opportunist trying to milk the controversy. I believe he came out against a genetic explanation for the black-white IQ gap, but strangely he overwhelmingly platforms more people on the other side of the debate. Anyways, good article.