Vitalik Buterin said artificial intelligence and data analysis have weakened the assumption that separating real names from wallet addresses can protect users onchain. Speaking in Shanghai at the 12th Global Blockchain Summit on September 23, 2026, the Ethereum co-founder said public transaction records and metadata can form identifying fingerprints when analyzed by AI. He cited Bitcoin’s original privacy model of separating identities from transactions and Zcash creator Zuko Wilcox’s comparison of public blockchains to "Twitter for your bank account," arguing that pseudonymity is no longer sufficient. Buterin advocated programmable privacy, in which code governs both asset-transfer permissions and access to specific data, allowing users to selectively disclose information such as sufficient funds or compliance credentials without revealing full balances or transaction histories. He also highlighted mixnets for improving transaction unlinkability. Ethereum’s privacy roadmap, last updated in August 2026, identifies keyed nonces and account abstraction as protocol building blocks for broader privacy applications. The remarks extend Buterin’s earlier warnings that AI systems can create data-leak, malicious-instruction and unauthorized-action risks, and reflect a wider shift toward cryptography that protects information as well as assets.