GNUnet is a free software framework for decentralized, peer-to-peer networking and an official GNU package. Developed by Christian Grothoff
License: Open Source
Matrix is an open protocol for real-time communication. It is designed to allow users with accounts at one communications service provider to communicate with users of a different service provider via online chat, Voice over IP, and Videotelephony. Developed by Matrix.org
License: Open Source
GNUnet focuses on decentralization and privacy, making it suitable for users prioritizing anonymity and resistance to censorship. In contrast, Matrix.org offers a more user-friendly real-time communication platform that emphasizes interoperability and broad adoption, albeit with some privacy trade-offs.