Platform mailbox lock‑in

Major mail platforms are quietly removing legacy, decentralized retrieval methods (POP3/Gmailify) and steering users toward vendor‑managed access (app/IMAP + cloud features). That shift reduces user control, consolidates spam/metadata filtering in a single corporate stack, and breaks common‑place workflows for multi‑account consolidation. — If replicated across providers, mailbox lock‑in erodes interoperability and user sovereignty over personal data, reshaping competition, privacy norms, and the economics of email as a public communication layer.