Why do I have to re-prove my identity at every regulated app?

Every exchange, lending protocol, and DeFi front-end requires a full KYC document submission even when you passed the same check last week at a competitor. Your passport scan ends up distributed across dozens of custodians, each a separate breach liability. Zero-knowledge KYC proofs can verify compliance claims without re-sharing raw documents, but no interoperable standard binds them to FATF-compliant audit trails. MiCA 2026 explicitly calls for reusable identity proofs for CASP licensing yet specifies no technical format. The gap between regulatory expectation and a working portable attestation primitive is still wide open.