I think this is true that credit/debit cards will not have much value after the launch of CBDCs,on a norms technology has played a vital role in the global world and as it evolve people tend to adopt the New system of technology so I think after the launch of CBDCS debit/credit cards won't be of Great use anymore depending on the usage and likeness of the new technology.
And by the way,most person like myself even with the fact that I have my credit cards I tend not to do transact with it and prefer online or my mobile banking instead,so definitely it'll surely hit hard on credit card or debit card as well.and it can also be in use cause not everyone is comfortable with this Mobile banking of a thing.
as much as I like the convenience of credit card, I just never feeling safe using credit card, like you, mobile banking is always my way to go, the reduced risk of unauthorized transaction is honestly a really huge advantage.
so I don't know why people are fancy about credit card so much, while it's just abstracted debt in a nutshell, which often people got themselves into trouble by overspending.
the more advanced technology and the higher rate of online transaction should instead make credit card obsolete.