You have to show violence the way it is. If you don't show it realistically, then that's immoral and harmful. If you don't upset people, then that's obscenity. ↗
I don't really know what is shocking. When you tell the story of a man who is beheaded, you have to show how they cut off his head. If you don't, it's like telling a dirty joke and leaving out the punch line. ↗