The fact is that Hitler and Stalin both greatly admired each other, despite being bitter enemies....Hitler would go out of his way to insult Churchill and FDR, but he never personally directed insults towards Stalin personally.
You are correct. They were both far more similar than they were different. The reason the went to war was to dominate Europe, rather than any ideological difference. Jonah Goldberg aptly described them as “...two dogs fighting over the same bone.”