RIGHT!!! Riot has turned on End-to-End Encryption by default for all private conversations, and Cross-Signing device verification has landed and is live (and 🤞 performant!) 🎉🎉🎉 Huge amounts of work went into this: https://matrix.org/blog/2020/05/06/cross-signing-and-end-to-end-encryption-by-default-is-here has the overview.