From Apple's statement[0]:

> The first assigns the user an anonymous IP address that maps to their region but not their actual location. The second decrypts the web address they want to visit and forwards them to their destination. This separation of information protects the user’s privacy because no single entity can identify both who a user is and which sites they visit.

Apple is not saying nobody can deanonymize you - they are being very careful to only state that no single entity can deanonymize you. Hence you should still assume this is not a good protection against any entity with subpoena power, or the ability to compel the cooperation of Apple and their 3rd-party egress relay providers.

[0]: https://9to5mac.com/2021/06/07/apple-icloud-private-relay-fe...