Did a Holocaust happen ?"
ProPublica describes how easy it was. Editors paid thirty dollars to access these groups. It took fifteen minutes for Facebook to grant permission. The editors informed Facebook, and then the anti-Semitic categories were removed . Apparently, these categories were automatically created by an algorithm, not by humans.
Apparently these categories were created automatically by an algorithm, not by humans.
Sorry, we can't do anything about it. There are people on Facebook who post anti-Semitic texts, and these texts are picked up by our algorithms. The " we're just a platform " logic.
Preventing narrow-mindedness
It is indeed remarkable. Those same algorithms were able to detect the classic photo of the Napalm Girl from the Norwegian news website Aftenposten , because there was too much nudity in the image phone number list Facebook, incidentally, admitted its gross error shortly afterward and allowed the photo to be included in the article. And to prevent such narrow-mindedness in the future, a programmer was likely instructed to adjust the algorithm that recognizes nude photos, and perhaps allow for a bit more context.
But don't start arguing that algorithms were responsible for the anti-Semitic categories that can be used to promote swastikas and Mein Kampfen.
No one but humans is responsible
People are responsible—programmers at or working for Facebook, and no one else. And they've apparently left too much freedom to the automatic generation of audiences. They've allowed the creation of collections that appeal to—let's say—bad people. Racists, child pornography enthusiasts, Jew-haters, rapists, cigarette manufacturers, you name it.

Another example, also from Facebook
Last month, it was revealed that during the 2016 presidential election, a series of more than three thousand ads worth $100,000 were purchased on Facebook by a Russian fake source. A troll who presented Facebook users with contradictory messages about the rights of African Americans, including Black Lives Matter, while simultaneously making it clear to other readers that these groups are a growing threat to society.