In the Blunt Speaking old days, that was called
“Idiot-Savant”.
Nowhere in the article did I read that “Negro Tom” was ever able to benefit in a material way from his fine talents.
I didn’t read that he had a nice home or decent clothing or anything. I mostly read that he was held up for exhibit and amusement like a Dog who can toot Jingle Bells from bike horns. Some things, some social attitudes take time to change, quite a lot of time.
Do we know if he was generally happy or not?