There are a lot of issues with your post imo.
First, cash is going away, soon. Sweden has done it years ago. Europe is now playing catch up.
Second, a universal digital currency will remove all system heterogeneity. Yes money is already digitalised, but across several proprietary environments. I can and have set up several accounts across several banks so my spending cannot be fully tracked by a single corporate entity. This will be moot once everyone has to use the same harmonized system.
Third, one of the sponsors of the universal European currency has been caught talking about time limited digital currency. As in, spend your money or it just disintegrates after a set amount of time. Which really destroyed a lot of trust in the endeavour