I think this will attract even more new investors, because they will stop being afraid of digital currencies.
It has nothing to do with each other, because the CBDC is a digital currency issued by the central bank of a country and is actually just legal digital money. People will not change their opinion about BTC because one day they will start using the digital dollar or the euro, because no matter what those currencies look like, it is still just a centralized system that is the complete opposite of Bitcoin.
It would even push more people towards cryptocurrencies because they will have the freedom to move the digital Centralised coin across the internet to exchange for whatever desired goods to purchase. E.g people in China who have always wanted to purchase Bitcoin can easily buy using the digital yaun.
You live in an imaginary world of your own, because the digitalization of national currencies only means even greater control over the money that anyone spends - it means that the Chinese will certainly not be able to buy BTC just because they will have a digital yuan - on the contrary, it will be practically impossible for them with all these prohibitions they already have.