I don't even know if you know what you're talking.

First, cash is going away, soon. Sweden has done it years ago. Europe is now playing catch up.

Please refer the OP's post in this thread.

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.

That's the privacy problem the OP's saying.

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

How's that related to my post?