Quantum-resistant cryptography is no longer a research agenda item — it is an infrastructure procurement decision, and payment networks running HSM estates, tokenization vaults, and interbank messaging rails need migration timelines on the capital plan now. The NIST post-quantum standards finalized in 2024 set the clock; Sibos 2026 marks the moment industry consensus shifts from awareness to accountability for operators who have not yet audited cryptographic dependencies across their settlement and authentication layers.