We have a few former airline dudes who go through UPT and become military aviators. While most of them have excellent basic airmanship and instrument knowledge, they are no different than a brand new straight out of college type UPT grad when it comes to the more advanced tactical flying.
Also, the problem, as stated, is not a lack or young volunteers to become pilots, it’s getting the experienced ones to stay around and run the enterprise not to mention mentor and teach the young guys.