If Elon Musk cut off his arm, all of his money would pour into making cool cybernetic arms that would help disabled people, he'd be able to pretend he was "Real Life Iron Man" again, and he would find it harder to use his Twitter account.
Win Win for everybody.
The resulting cybernetic arms would only be capable of autoerotic asphyxiation, and even that wouldn't be intentional. I guess if you get lucky it might fall apart before it manages a Full Carradine, but that's not the kind of risk that makes it into my gooncave.