This article examines Twitter’s mutation into X under Elon Musk, analyzing its shift from a mainstream platform to a far-right-aligned space. Using a dataset of over 1,500 events related to this transformation and a novel conceptualization of institutional change in trust and safety systems, we argue that three processes characterized X’s approach to content moderation: the political simplification of Twitter’s governance ecosystem, the centralization of power in Musk’s hands, and the repurposing of governance mechanisms to enforce Musk’s personal ideology. Together, these processes resulted in what we conceptualize as platform illiberalism, an emerging regime whereby illiberal-esque logics reshape speech control internally while supporting illiberal actors externally. We argue that X represents an unprecedented fusion of social media and authoritarianism, with close ties to and potential implications for democratic erosion in the US and beyond.