tl;dr: Dutch bank ASN's Wero operator EPI justifies blocking GrapheneOS by claiming hardware key attestation can't prove OS integrity—but that's factually wrong, since Android's attestation certificates include verified boot state and signing key hashes that GrapheneOS publishes for exactly this purpose. A developer on the other side admits they also gate on Play Integrity rather than key attestation, not for security reasons, but because parsing X.509/ASN.1 and maintaining a key hash allowlist is harder to defend to auditors than simply pointing to Google's verdict.