Looks like the comment was updated? I see a different one now.
To reply to
> Both of these have been in place for a very long time.
> Ever use a debit card to buy something?
No they haven't. Debit card balance isn't a deposit at the central bank - it's commercial bank money (i.e. a liability of the commercial bank, not the central bank).
Retail CBDC is digital central bank money held by the public (retail). So it would be the public holding a central bank liability
