Those same "tight currency and economic controls" apply just as much to cryptocurrencies as they do to Visa gift cards. There's nothing better about "Venezuelans should've used cryptocurrency" versus "Venezuelans should've used dollars".
But beyond that, people have the right to determine their country's monetary policy independent of, say, Bitcoin devs, Facebook executives, or a foreign government (ex: Venezuelans using USD), and it's hard for me to ignore the vague scent of opportunism here. The solution to corrupt governments is not "get rid of all governments", it's "get rid of corrupt governments".
US has often taken advantage of its dominant world currency position. For example, massive amount of QE that eventually gets absorbed worldwide with little inflation in US. Similarly "petro dollars". The bottom line is that if someone is allowed to print currency at whim, they will.