Where is the evidence that most deaths in the USSR were caused by Operation Barbarossa?

I don't buy that most of the deaths in the USSR were caused by the Nazis. That's just a non-sensical talking point designed to whitewash the legitimate brutal history of the USSR. We get it, you're offended that nobody trusts communism.

We have a good reason to. It's always brought dictatorship. Why do you need to make up stories about Nazis being the major cause of deaths just to make excuses for the failed system that communism is?