I am one of the folk in the inevitability of cryptocurrency camp (not btc or any existant coin, though) but that world is one where it becomes very easy to correlate wallets, or at least where the funds come from, with the person making the purchases.
For everyone who wants anonymity they can keep using bitcoin and gold after fiat paper and coins are gone.
If you believe that, you're going to be shocked when the vast majority of people switch to cashless systems, and cash will only be used for criminal activity, and then cash will become criminalized.
The solution isn't to preserve cash. That's doomed to failure.
It won't happen if enough people fight it. You should value privacy and have a healthy distrust of both banks and governments.
Here are the heartening results of an EU survey conducted earlier this year about restricting payments in cash[0]. In short, 94.9% of respondents oppose restrictions on cash payments. 86.9% believe that paying anonymously is an essential personal freedom. That's the spirit.
There is no regulatory tracking of bank note number to who withdraws it. None. An incredible and incredibly pointless mess. ATMs do read them however,for the just-in-case scenario.
In bank robbery stories, sure "A million in used notes" sounds nice, but that's because a net would have been thrown down, or specific attention drawn to a serial, but in most cases, no. The regulatory burden would be far too surreal.