I think Kim Jong un has more pressing matters to worry about than bitcoin, for example witch family should he send to kolkhoz, who to kill accuse for spying, who can threat his position in the next 20 year and to kill him now or later, and so on
Indeed, tryrants are not very bright i would say pretty dumb most of the times. But they are powerhungry so that give them a sort of "appeal" from their people.
If they would be bright they would not be tyrants, because most of the tyrants end up on a rope.