Vitalik Buterin welcomed Signal's effort to let users register without a phone number, calling it a meaningful privacy upgrade for encrypted messaging. He said the shift would reduce dependence on a concentrated identity system, make location-based discrimination harder and limit government pressure to block users by nationality. Buterin also argued that phone numbers are a poor root of identity and that pseudonymity is increasingly fragile in practice. He said timing, contact patterns, message frequency, size and AI-assisted analysis can expose who is communicating, making per-message unlinkability a better privacy target than long-lived pseudonymous accounts. The comments build on Buterin's broader push for privacy tools across messaging and Ethereum. Signal still has not officially confirmed the feature, but it has acknowledged that phone-number-free registration is frequently requested. He also pointed to privacy-focused alternatives such as Session and SimpleX Chat, while noting that spam and denial-of-service protection remain unresolved obstacles for systems that avoid phone numbers.