Answer:
Dwight faced zero obstacles at NASA because he was never there, the story that he was selected as an astronaut and then blackballed is a modern myth without any reality. NASA never picked him, based on non-racial reasons such as his test pilot class standing, on his expressed attitude that pilot skill wasn't important because he expected the capsules to be entirely remote controlled from Earth, and on him being several inches too short to see out the window and safely fly the Apollo Lunar Module anyway, it had nothing to do with his skin color.
Explanation: Some stories are created and spread for political reasons, not for accuracy.
