Many actors too old to portray infantrymen...
I was an infantryman with the Marines in Vietnam in 1968. I tend not to nitpick while watching a movie but after its over I will mull over its nuances.
In Pork Chop Hill too many of the infantrymen looked 35ish if not 40ish. George Peppard, a Detroit native like me, looked the age part but many didn't.
Like Gregory Peck and he looked younger than his 42 years in Pork when it was shot, but too old to be a 1st Lt. Willie Stroud also looked more like an Army lifer sergeant than the junior enlisted man he protrayed.
By 1953 when the battle of Pork Chop Hill took place the US Army was filled with young draftees.
If you enjoyed the movie, read the S.L.A. Marshall book.