Platform Constraint Theory formalizes the shift from rule‑based to architecture‑based governance in the post‑open‑web era. Instead of relying on explicit policies or moderation, platforms now govern through structural limits embedded in their interfaces, affordances, ranking systems, and representational grammars. These constraints define what users can express, perceive, or achieve, turning participation into a function of environmental design rather than individual agency. The essay maps the multi‑layered “constraint stack”—interface, semantic, temporal, social, and algorithmic—and shows how these layers silently shape behavior, visibility, and epistemic outcomes. Platform Constraint Theory reframes platforms as constraint regimes that govern possibility itself, revealing how power operates through the architecture rather than the rules.
Signal Rupture (Sun,) studied this question.