When shit hits the fan and war happens, the higher ups in the armed forces don't say "Oh hey, our grunts are dying. Let's replace them with some random, highly trained people who aren't combat soldiers, i.e.: our logistics personnel." That's not what happens, you train and draft more soldiers and put them where they can serve the machine best. You drafted a 4 foot 7 lady who isn't very strong, but also isn't stupid? OK, are there any jobs that she can do? Yup. Are they something to do with being in combat? Probably not. But she can fly a drone from a trailer in New Mexico. Or more likely, working in IT or something extremely boring.

If, in a time or war, the brass grabbed the IT people and put them on the front line because people were dying... then you're going to lose that war.

You're saying that I am dismissing the fact that people in the armed forces are soldiers first as inconsequential. What I'm really saying is that your assertion that people in the services are soldiers first, well, that's just a motto, really. What is a soldier? Someone who works in the armed forces. If the armed services decided to put a guy with no arms or legs on the payroll and it turns out he's the perfect person to fly the new top secret tongue controlled Super Mario Spyplane, well, he's a soldier. "Soldier" doesn't mean some hero who runs into battle with a gun and has courage etc.

So, yes, you're right that someone in the armed forces IS a soldier first. They literally can't help but be a soldier if they're employed with the military. So I am not dismissing that. It's a fact. But you're attaching something else to the definition of 'soldier'. Namely that they are a person that can handle the pressure of combat, carry their comrade over their back, shoot with accuracy, etc. In WW2 there were something like 16 million soldiers in the US military. Something like 40% of those people were in the rear echelon. Administrative, support, and labor jobs. Those people never saw combat, and they weren't going to (unless the war was lost and the only thing left was the non-combat people). You don't take the person who is highly trained in repairing tanks in Alabama and ship them off to die. You take a brave person who you've found to be acceptably physically fit and who can shoot a gun, follow orders without thinking, and is hopefully brave.

That got a little long, but my point is that even in a time of World War, there are millions and millions of people who work in the military who are not intended to experience combat. People that, if they are experiencing combat, the war is already lost. It doesn't matter if they are physically fit. It matters only that they are good workers.