I reject that completely.
They are each on a separate plane compared with others...a separate plane of their own uniqueness.
There are aspects of evil in the Holocaust not inherent in the GULAG system: systematic industrialized extermination, based on religion/race.
I agree that they are all on a separate plane, and that the gas chambers are the synthesis of the specific evil of the Holocaust.
But you just did something very similar to denial of the gas chambers by Williamson: you denied the extermination aspect of the Gulag based on a book that you read. Does it cross your mind that perhaps Hannah Arendt’s book has been likewise rebutted? I could probably cite from Lenin, Trotsky and Stalin regarding their intentions as they formed the NKVD.