Decentralized social networks and the future of free speech online

Decentralized social networks like Mastodon and BlueSky are trending topics that have drawn much attention and discussion in recent years. By devolving powers from the central node to the end users, decentralized social networks aim to cure existing pathologies on the centralized platforms and have been viewed by many as the future of the Internet. This article critically and systematically assesses the decentralization project's prospect for communications online. It uses normative theories of free speech to examine whether and how the decentralization design could facilitate users’ freedom of expression online. The analysis shows that both promises and pitfalls exist, highlighting the importance of value-based design in this area. Two most salient issues for the design of the decentralized networks are: how to balance the decentralization ideal with constant needs of centralization on the network, and how to empower users to make them truly capable of exercising their control. The article then uses some design examples, such as the shared blocklist and the opt-in search function, to illustrate the value considerations underlying the design choices. Some tentative proposals for law and policy interventions are offered to better facilitate the design of the new network. Rather than providing clear answers, the article seeks to map the value implications of the design choices, highlight the stakes, and point directions for future research.