This is correct. The Holocaust happened, and it was as bad as they say. Rudolph Hoess, the guy who ran Auschwitz, estimated 2 million were killed at that site alone, but he was not permitted by Nazi leadership to keep records because the exterminations were kept from the public. Much discourse about how to hide the killings went on behind the scenes.

However, it is also being exploited today for sympathy, drama, and money by people who were not in it.