@katharsisdrill Did you see the NGI Taler project? That’s the first where I think that it really does things right:
https://nlnet.nl/taler/
The goal is a digital currency with the privacy properties of buying in a shop with cash.
They took up GNU Taler (micropayments where the sender is anonymous to the bank, but the receiver — shop — is not, so it can be taxed reliably) and are scaling it up for banks.