EU supervisors warn quantum computers could break blockchain security

The significance here is timing rather than novelty: supervisory authorities are flagging a cryptographic risk that core protocol communities are already scheduling work around, which turns a theoretical concern into a governance and upgrade-coordination question. It affects public networks and the institutions holding exposure to them, since migration is a chain-wide effort no single operator can complete alone. The open question is whether developer-led timelines and regulatory expectations converge, and how networks handle the transition period when old and new cryptography coexist.