What people care about is the situation's impact on people. Topics and themes are other words for situations. Abortion is a topic. Communism is a topic. Freedom is a topic.
Religion is a topic.
Unconditional love is a topic. You might have strong feelings about any of these, but topics are nothing until you show the impact they have on people. A movie about freedom might have a lot of noble talk and maybe some saber rattling about freedom, but it has no impact. However, take a World War II Hungarian Freedom Fighter who fled for his life to this country when the Soviets took over. He calls his mother weekly and gets a steady torrent of news about his families' repression because of him.