Only to the extent that central banks will be successful on all three fronts I have mentioned, they should not fear outside competition. And at the same time, central banks should be open-minded with respect to the new technologies underlying these developments, as they can potentially be of use for themselves.
Somewhat related to this, the idea has been floated that central banks could issue their own digital currency. Let me be clear from the outset, a central bank digital currency is conceptually fundamentally different from the so-called crypto currencies. It would just be another form to hold the same money.