Far more people died in the Gulag, than in the Nazi Concentration Camps. Indeed, the Soviet Communists were even more fiendishly savage about how they captured, tortured, and killed their victims.

Twin Ruler fails to realize the difference between the Holocaust the Gulag. Firstly, only 1.6 million were reportedly killed in the Gulag over the several decades of its existence, and possibly at most 3 million to give a very generous figure to those that may have died and weren't reported. There weren't some tens of millions as Twin Ruler tries to claim across the internet in the Gulag, in fact very seldom were there any more than a million in the Gulag at any one time.
The Gulag itself were forced labor camps designed primarily for criminals, such as murderers. They weren't much different than "chain gaings" in the US, only with harsher treatment, and yes inhumane treatment. There was little hesitation for executions. The Gulag was bad, yes, but it wasn't an act of genocide. There weren't any specific types of people being systematically destroyed. Genocide is the systematic destruction of a people because of their race, religion, or politics. Some 5 million died from brutality, execution, horrifying lab tests and weapons tests, malnutrition, gas chambers, burning, etc etc. The list goes on about the horrible things that happened to the Jews. Hitler sought to destroy the entire Jewish race in Germany. The Gulag was not a center for such actions.
What Twin Ruler may be doing is accounting the millions that were killed by Stalin during the Purges, some 20 million were estimated to be murdered, but nobody knows the true figure, it could be more or less. This could be considered genocide, but this is not the Gulag.
To try to compare the Gulag to the Holocaust is a display of ignorance and an insult to anyone who survived such horrific acts.