There's a reason why the saying goes as "follow the money" and not "follow the mail". Think about why and you'll understand why CBDC is Orwellian worst nightmare.
one secret there is, they can photo record every source addr<->dest addr from the post item face, for some or all of the delivery, for years and years without fail, keep those records, and then do investigative work from that.
They never open the package, and technically, they are quasi-public.
Public enough that they can't play fast and loose like everyone else, but private where it matters in terms of not having literal Federally administered databases all just eafer for the reaping.
The USPS isn't quasi-public, it's fully public, an “independent” (meaning it has an Presidentially-appointed, Senate confirmed board with limits on degree of single-party domination) federal executive-branch agency.
The fed is quasi public too? It’s actually less public than the postal service, the postal service is a fully public agency, the fed is partially governed by private banks.
Nonetheless, given that the individual regional banks are have directors that are elected by the member banks, control over certain levels of fed policy are in a sense private, whereas that is nowhere true for the postal service. At least not to my knowledge.