Private keys are not proof of ownership, they are a technical implementation detail. That crypto has been poorly designed so that keys are all people have to pr

Private keys are not proof of ownership, they are a technical implementation detail. That crypto has been poorly designed so that keys are all people have to prove ownership is a failure of design but doesn't fundamentally change the divisibility of ownership and access. This is easily observed with a shared wallet, for example coinbase's. If an employee stole their keys, I assure you that employee would enjoy a jail yard view for the next lifetime.