I'm going to ghost a guy because of his taste in films
What's wrong with his taste of films?
He sees movies that are very violent.
Ghosting someone on his taste of movies is very rude.  You don't have to like everything about someone else to get along.
Well, I'm also ghosting him because of his character.
It sounds like the problem runs much deeper than your taste in hobbies, and maybe you are right to end this relationship.  However, just cutting off contact with someone is wrong, and it leaves them confused and worried.  Let your boyfriend know that you are not compatible, and that this is for the best.