The data is the contents of the transmission. The metadata is the data describing the transmission. So yes, the phone number, date/time, etc, are metadata of the actual communication.
The AC above is correct actually. I am a Marine who has spent most of his time in joint-service environments and I know of those in each service who have gotten waivers for various "disqualifying" issues. You may join if you are gay, but not openly. "Don't ask, don't tell" is still in effect, although perhaps not for long. Asthma is not automatically disqualifying, as the AC mentioned, if it is mild enough that you can still fulfill the physical requirements. Credit issues are looked at on a case-by-case basis, and again as the AC mentioned, there is help available within the military community itself. Yes, poor vision can disqualify you, but it depends on the service you plan to join and the job requirements for the work you will do.
You are absolutely correct in saying that the military has to recruit from a smaller pool than other organizations, but it is not as severe as you make it seem. I'm sorry that you had a bad experience and that you were not given the opportunity to serve our country in the fashion that you desired, but please don't let it cloud your judgement. We work with many civilian contractors as well, and they are paid quite well to work with us and to be the resident experts on various topics.
"The best, most talented" is subjective, of course, but the military is actually producing highly skilled and capable workers in the cyber security field. Most of the budget is not spent on equipment, but on training. There are many servicemen and servicewomen who go through NSA training and work closely with their civilian counterparts. If they decide not to continue a career in the armed forces, they will often make the smooth transition to one of our three-letter civilian intelligence agencies. Of course, there are some who also turn to the corporate market and are paid a pretty penny for their skills and security clearances there.
Also, without divulging anything classified, I can only say that our military HAS to stay on the cutting edge of technologies and skills to maintain our military superiority in this day and age. I am often amazed at our capabilities and they continue to expand every day. The history of computing has been tied to military interests from very early on and the military continues to push the envelope. What better place to learn about emerging technologies than the place that requires them?