It's pretty hard to get objective and accurate count here; unlike Nazis, Soviets (and I imagine Chinese et al) did not keep meticulous accounting even of people specifically executed, let alone of those keeling over in prison camps despite technically being only sentenced to imprisonment). Solzhenitsyn himself said, at least initially, that his numbers are extremely approximate, based on what personal research he could do and that he hopes future historians will do better.
Having said that, 60 million killed in USSR alone would seem highly suspicious. 60 million repressed sounds quite feasible. And as Stalin would acknowledge (death of one is a tragedy, death of millions is statistics), in a way it doesn't really matter -- communists killed as many, if not significantly more, people as Nazis, but because they usually did it to their own population, and weren't defeated by an invading army, they escaped anything resembling Nuremberg Tribunal, and to this day Nazi defenders keep quiet in decent society, but Soviet apologia is pretty rampant.
Having said that, 60 million killed in USSR alone would seem highly suspicious. 60 million repressed sounds quite feasible. And as Stalin would acknowledge (death of one is a tragedy, death of millions is statistics), in a way it doesn't really matter -- communists killed as many, if not significantly more, people as Nazis, but because they usually did it to their own population, and weren't defeated by an invading army, they escaped anything resembling Nuremberg Tribunal, and to this day Nazi defenders keep quiet in decent society, but Soviet apologia is pretty rampant.