As Bloomberg points out a cryptocurrency run by central banks might be better than one run by Facebook and friends. That still doesn't make it a good idea.
Rather than debate with Zuckerberg, some central bankers seem to be mulling the idea of grabbing the Libra idea for themselves and setting up an alternative. If the problem with such a currency is Facebook, why not make one yourself that’s Facebook-free? The Bank of England governor Mark Carney floated last month the idea of a “Synthetic Hegemonic Currency,” one backed by a basket of reserve currencies but without the “fundamental” problems raised by Libra. This week Benoit Coeure, a European Central Bank executive, called on other central bankers to join forces and look into issuing digital currencies to fend off the private stablecoins.