Re: But why is this necessary?
If you look at documents about CBDC - what they peddle as digital cash is nothing of sorts - it's not private nor anonymous and its history can be tracked with fine detail.
Being able to track money through digital exchange is probably quite a useful crime fighting tool, which is partly why dodgy deals involve suitcases of used notes to hide the exchange from the Police / authorities
Such system is surely going to have a feature to hide transaction trees and it means it will work both ways - government and associated organisations will be able to hide their criminal enterprises, but they will be able to crush anyone going against them with ease.
It's not about fighting the crime or making people lives easier. They just crave that power and wealth and they will be able to steal our money with a press of a mouse button.