Earlier quoted context omitted.
It's been around a lot longer. We've called it Shell Shock, War Neurosis, Battle Fatigue and several other things. It's well documented. PTSD, imo, is just another layer of indirection when referring to trauma. It's name provides significantly less meaning than something like "shell shock" which gets right to the point of the matter. PTSD was certainly appreciated. Patton famously got a reaming from Eisenhower for ho…
"Shell shock" becomes a euphemism when you're talking about people traumatized by something other than artillery. PTSD is more general, and therefore more precise in the general case.
Regardless, PTSD is a terrible term because it's non-descriptive. It also makes it more difficult for a person to be empathetic to a sufferer of PTSD because it's not an on/off switch and more of a spectrum. A term like "shell shock" illustrates the actual trauma and enables people to be understand better why a person might act the way they do. It is often easier for a person with PTSD to describe themselves as a "victim of X" or "experienced Y" because the term is so disconnected from actual meaning. It belongs in medical textbooks, certainly, but in spoken language it's worthless. A perfect example of jargon.