The old mantra of possession is 9/10ths of the law is and always has been false. If i have something i own it. That is the one fundamental truth. Now someone can come and try and take it back from me by force (Person, Court System, Rebels, Corporations) if they can exert more violence on 'me' than i can exert on 'Them'.
The problem with crypto is the 'keys' are what crypto is. No nationstate can come and take that away from me. They can kill/imprison/fine me, but then neither of us will have it. You would have to hack/fork the chain for that to happen (Which has happened) or find some social way around it (If i have it on a centralized exchange, if i have a hackable hard drive, found my keys on AWS, etc etc.) Additionally, with things like Monero, and tornado swap good luck trying to find them.