I'm glad you wrote that last observation. General Yeager also reportedly had an abrasive personality. As do many in aviation (including this writer).
Neil Armstrong, along with Bob Hoover, is regarded as one of the very best "engineering test pilots." He may have been the best pilot with the best education, ever. That's not just my opinion.
Yeah, they knew the astronauts would all be public figures by default, and they didn't want someone who might haul off and tell Charles Collingwood or Frank Reynolds to f off on live TV.