The article mirrored very closely many of the reasons that I've heard offered by some of my friends. Another thing to think about is the fact that the demographics of the general officer corps will reflect accessions from 2-3 decades ago. We can see a similiar situation with female general officers where you are seeing an increased number, both in numbers and highest rank achieved, based on policy changes made decades ago.

Another consideration that will have an impact on the demographics a few decades out are the opportunities available for the most competitive minorities. Given the choice between a service academy or ROTC with a service obligation and a scholarship through a masters degree at an Ivy League university or other top tier university, the military simply cannot compete.