Tell that to cadets. Their branch/service commitment is based on their OML (order of merit/rank in class). More than a few don’t get to do what they want to do. This year, USMA branched 81% of the class of 2019 into combat arms. Not all 81% wanted to go that route. 
Again, what my child’s or anyone else’s employment prospects are is irrelevant to the fact that ROI was never a consideration in our education decisions. However, if you are a person who considers guaranteed employment a priority, the military may be a great option.