On one hand, this is the type of overbearing authoritarian policy one might expect from Maduro which ultimately led venezuela to ruin. Its a protectionist policy towards china's native currency the yuan. It will restrict innovation and growth which could be harnessed from crypto currencies. Similarities between china and venezuela in terms of government structure and policies could be evidence china will never become the world power the establishment imagines.
On the other hand, this could be justified as preventing capital flight. The ends justifying the means of preventing an outflow of currency through china's borders which could ultimately weaken its economy and impede growth.
And so this may be where jokes about economists and their hands come from.