I live in San Antonio and know people in the service now. This is BS. The exact opposite in fact.
Quoting: My Fear Do you? Are any of them Colonels or above?
San Antonio does have a lot of military, but a fraction of places like Fayetteville.
The people who were replaced and railed into retirement or worse were Colonels and above, which make policy in the US military.
One of the most famous, to be retired early was an Admiral who launched fighters to help support Bengazzi embassy against the President's orders.
Another was General McCrystal who was retired early for saying Afghanistan was a hopeless cause unless tens of thousands of more troops were deployed.
Also, General Patrieous. What happened to him, huh?
San Antonio is also the home of the Air Force's enlisted basic training. Talking to grunts doesn't give the picture.
What it tells you is what it has become.
So, all that being said...
There is some Credence to what you say. Most military who are not lifers are ages 17-26.
Those born in that time, were 3 to 6 years old when the war on terror started.
Also, culturally, many of them faced serious inculcation during their school years, and were taught that enabling was more important then independence and freedom of choice.