Some fans out there actually like Moon Knight and wouldn't mind seeing a Marc Spector movie. One fan in particular questioned Marvel Studios director James Gunn on Twitter about the possibility of a Moon Knight movie or even if Moon Knight could appear in Guardians of the Galaxy 2.
While James Gunn responded by stating he has a great idea for a Moon Knight movie, he did say he won't be directing. Maybe it's possible that James Gunn told Kevin Feige and Marvel Studios his Moon Knight idea, and some time down the line (Phase 5??), Marvel Studios could go with a Moon Knight movie.
If you are not familiar with the character, you are probably not the only one as the comic book never sells well, but Moon Knight sees his origins related to the Egyptian moon god of vengeance, Khonsu. Long story short, Marc Spector agrees to become Khonsu's avatar on Earth and becomes the
dark white knight, Moon Knight.