People like that resemble modern day "wise men" or sages to me. Our middle school janitor was a math PhD who left academia, became a farmer for decades, and eventually our janitor.

He rarely told anyone his credentials. Most people thought he was just some old man. I watched parents and teachers be rude to him, but he'd always smile and be polite. Some of us used to help him from time to time. He was very kind and would always listen to our kid-sized problems while we worked.