So, what does he do for a living? Odd jobs. He has held one steady job in the decades I've known him. This is because he has poor social skills (although I've tried to help him learn the ropes of understanding people) and because he finds accepting other people's mediocrity frustrating as he politely tells them their errors - and conversely, they resent his cleverness.
I was lucky enough to work with someone similar to my friend about 10 years ago. As his boss, I sat down with him and basically said "you are very clever but you are also ignorant. You change external interfaces that drive significant changes to the rest of the system. You must stop it for the sake of the project". He exploded and told me to "f* myself" in front of the project team of ~100 to hear. Two hours later, he apologised and thanked me for my honesty and wisdom (translation: courage to tackle the wild brumby). When I saw him a few years ago, he was a different person. He thanked me for my kindness and patience back then, which meant a lot to me.
To wrap it all up: some people truly March to the beat of their own drum. I thrive on these people.
Good luck. I hope you find your groove. No one else will find it for you, unfortunately.