I'm loosely aware that there's a Marxist Film Theory school, and that obviously there were many filmmakers and theorists who were Marxists in history, but I can't wrap my head around how one would specifically apply Marxism to film critique and production.
I also can't find any understandable explanation. Could somebody ELI5?
I assume you've read the Wikipedia article for Marxist film theory since that's the obvious search engine find, but have you also looked at Marxist literary criticism? That page breaks things down a bit more in the last section.