There is are potential upsides to a CBDC which should be much faster speed and much lower transaction costs.
There are many downsides real and potential, including of course federal intrusion and spying on individual and organizational transactions. I would argue there are 1st and 4th Amendment concerns and simply would not trust that the ledger keepers would respect freedom of association and freedom from warrantless searches of financial data.
Now add another factor - Visa, Mastercard, Discover, Amex, Goldman Sachs and other card issuers love their 3% merchant fees and love the interest they charge. I am not sure how they fit into a CBDC system but somebody will be lending money on that blockchain. And the banks love their wire fees and other fees. Blockchains only charge fees for moving money and generally speaking it has been quite low (though relative to the token, it could be high it should really only cost a few cents per transaction).
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