They may only halt its adoption process, other than that, they are doomed to fail is they think they can replace BTC with CBDC.
Bitcoin does not replace fiat currencies, won't replace CBDCs, won't replace altcoins, and oppositely CBDCs won't replace Bitcoin or kill Bitcoin.
I am optimistic with Bitcoin future and I imagine a scenario in future that people globally will use fiat currencies, CBDCs, Bitcoin and altcoins. There will be no absolute world with only Bitcoin to use. Even I am optimistic, I don't think it is realistic ultimate goal for Bitcoin growth and adoption, but I believe Bitcoin won't die.