Why It Took Meta 7 Years to Turn on End-to-End Encryption for All Chats

Meta is starting the full rollout of default end-to-end encryption for its Messenger and Instagram chats, after working toward the goal since 2016 and Mark Zuckerberg's 2019 promise. The feature is launching now for direct messages between two accounts, while group chats remain opt-in for now. Meta says it built the system on the Signal Protocol and vetted it internally and with independent experts, and it introduced Labyrinth, an encrypted storage protocol that keeps chat histories on its servers in a form the company cannot access. Law enforcement and child-safety groups have condemned the step, while privacy advocates have praised it.