As a career officer, I didn’t really care what the reasons were. It was painfully obvious that manpower was ever on the decrease during my 22 years, and the needs, wants and desires of the folks controlling the military forces were not on the same schedule of decline. Not to mention the long term downsizing vis-a-vis the ability to fight the two continent conflict,and the technoligizing of the military occuring also during this period which in some minds excused the downsizing.
Personally, I have always felt there had to be a balance between tech and manpower. If your total force is 300 ships or 300 airplanes, and they have a six to one or better kill ratio, you still reach zero when the 300 are gone, and tech is very expensive compared to bare bones. Additionally one of the opponents has unlimited manpower in comparison.
There is a military term or principal that explains how the loss of a any percentage of a military’s capacity is a far greater operational loss than the percentage loss. Are you aware of the term? It may even be a formula but I can’t bring it to mind.