Play Integrity checks if app was tampered with. Hardware attestations can only guarantee key's source and cannot be used to check app integrity.

I specifically referred to the remote attestation functionality in Play Integrity and that that can be replaced by AOSPs APIs, since the linked post is about remote attestation.

Play Integrity actually does both and passing remote attestation is necessary to pass Play Integrity at the strong level. Remote attestation is used for this level, since a modified OS could fool DroidGuard.

I'm sorry if my comment was not clear in what I was referring to.