Nazism vs. Communism
To understand why Nazism (a form of Socialism that murdered 12 million) is condemned worse than Communism (a form of Socialism that murdered more than 100 million people and enslaved countless others), one must find the source that is driving the narrative, and you will have the answer.
It is the same with the erroneous condemnation of Pope Pius XII, that he acted as Hitler's Pope. Find the source of the narrative, and you will have the answer.
VIVA CRISTO REY!