Engineers that work in defense/nasa/etc generally aren't on twitter, linkedin or facebook broadcasting, well, anything - you just don't hear about them unless you personally know some of these people. It's part of the job description to be private and avoid becoming a target of the media or a foreign nation. It also makes it difficult to stay in touch with colleagues when you're relegated to the rolodex-era of communication.

Quite contrary to your statement, this world might be 1000 times better if the same engineers working on government programs were to work in the commercial sector, pushing the boundaries of tech that is accessible by everyday people.