As you and others note, many Americans had, and have, a fondness for communism. Viewed in this light, it should come as no surprise that there have been so few films about the Holomodor.
Hitler and Stalin were allies and coordinated their attack on Poland. Then Hitler betrayed Stalin and attacked the Russian communist empire. It is easy to see that why communists and their supporters would hate Hitler. Pro-communism lends support to the making of anti-Nazi films.
To be clear, I am opposed to both the German National Socialism (Nazism) and international socialism (communism). Both ideologies are mistaken and harmful. Both led to the murder of tens of million innocent people in the 1930s alone.
What I am trying to address is why one genocide gets so much attention and another so little. I think the main reason is the fondness so many have for communism.
Keep in your mind that Socialists ARE really stupid.
Their destruction of Ukraine's Kulaks easily proves that.
Ukraine farmers were the most productive of Eastern Europe, and the political need to collectivize the farmers was exactly the opposite of the flexibility that Kulaks had learned to use to maximize their production.
So Stalin confiscated their harvests, didn't leave enough to survive the winter and all Russians starved the next year while Ukrainian farms sat empty and idle.
Then Socialists worldwide joined in saying: Rinse, Repeat.
These people NEVER learn.