This does not make sense.

CBDC’s will use blockchain technology, but will not be running on ethereum. There is no way that a central bank would choose to use a public blockchain for their platform. They will develop there own blockchain and it will not be public.

A public blockchain is a blockchain where there is no central authority that can change source code unilaterally. A private blockchain is the same kinda technology but someone maintains “administrator” level privileges.

So assume the fed realizes there is a problem. People are able to track drug transactions and see that the cia is holding the bag. To address “public concerns over a lack of privacy” they will need to unilaterally introduce a software update to hide some transaction and make sure people can’t peek into the cia’s drug trade.

Now if the fed was using ethereum, then they would need all the nodes around the world to update their software. This would be inconvenient.