Actors who have never seen action
I think the appeal of the war movies from the 1950s right through to the 1970s, was that many of the actors appearing in these movies had seen actual war action.
Many were highly decorated so they were actually living something for real.
So then we come to Dunkirk, a pile of utter cr** I wouldn't watch if you paid me. The sight of pretty boy Harry Styles acting as if he can feel the pain suffered by those involved with WW2 makes me just wanna vomit.