>Stealing most crypto money is about the dumbest thing ever, because all transactions (for most such currencies) are open to the public to scrutinise and de-anonymous at their leisure. And the police is included in 'the public'.

People keep saying this, and yet it keeps happening. You seem to have far more faith in the police than is warranted. Exactly how many investigations have ended in an arrest and recovery of funds from these actions? I'm guessing somewhere near zero for anything not directly involving government or corporate interests.