Perhaps. But 4 years is a very long time. And as I already indicated, the military is not a place for free thinkers or questioning authority. 4 years in the military would be devastating to many people.

Perhaps HR thinks that veterans make better employees, and from their point of view that may very well be true. Military people are used to a) obeying orders b) respecting paperwork c) respecting chain of command.
But I also know that military people ending up in ICT management positions can also end up causing big problems because they insist on having a rigid chain of command, and expecting people to obey without being open for discussion. And that is not the best way to lead a team of developers or system administrators. You can't herd cats.

The military is a good fit for some things and for some people, but also a bad fit for other things and other people. That does not mean I have disrespect for it, but forcing everybody through it for 4 years is not going to be a big success any more than forcing everybody through 4 years of college.

Different strokes for different people. A population that comes out of a cookie cutter is not that useful