Robert Downey Jr is the obvious case of a person who had a redemption arc, to simplify it he was a promising actor that got addicted to drugs, fell off, went to rehab and then became a huge hollywood big stsr known, even known for being Iron Man.
What real life person had a redemption arc?
Alfred Nobel invented dynamite (among several other explosives). The story goes that he read his own obituary and was called “the merchant of death”, and so left his fortune to found the Nobel Prize and leave a better legacy.