The other nice thing about cash is that it will still work even during power blackouts or cyber attacks. As a consequence, bank notes will probably always be around to some degree, if only as a contingency for unusual events.
This is money that is characterised by two features: (1) like banknotes in circulation, DBM is a claim on the central bank; (2) in contrast to banknotes, it is digital. Of course, DBM already exists. Commercial banks and some other types of institution hold digital claims on central banks in the form of deposits.