Mainstream social media platforms nowadays play an unprecedented gatekeeping role in public discourse. Through rules set by design, terms and conditions, content moderation practices and algorithmic systems, these platforms wield significant influence over individual users and public opinion. While the control over social media’s gatekeeping function was initially entrusted to self-regulation under the presumption of neutrality, it is increasingly acknowledged that their role is pivotal for the whole media ecosystem. This article examines the evolving policy landscape in EU media governance, offering a retrospective analysis of how policymakers have addressed social media’s “opinion power”— and a prospective analysis of the most recent regulatory developments, most importantly the Digital Services Act and the European Media Freedom Act. Finally, we conclude highlighting limitations, challenges, and opportunities of the EU regulatory framework.