I love sci-fi and read all the Dune books. They are making lots of movies where characters who were written as white are changed, even if it impacts the narrative. My point is that in Hollywood, this only happens if they think it will draw a bigger audience. They didn't think so this time. The decision to cast Chalamet was a good one. The film is raking in the money. It's almost always about money, especially with the big productions.