EU digital policy is currently one of the most ambitious and far-reaching endeavors to regulate the digital economy. Online platforms in multisided markets with digital ecosystems lie at the heart of digital technologies and business models. Among others, they pose new challenges with regard to the abuse of a dominant market position, thus ultimately reducing competition and innovation. This paper outlines an evolutionary approach to the co-evolution of law and technology with collective cognitive constructs and wealth effects as essential drivers (Eckardt (2001, 2008). It is then applied to the evolution of EU law in this field. After an overview of the evolution from telecommunication monopolies to the current digital platform economy, a case study presents firstly the Google Search (Shopping) case (2010–2024). Based on traditional EU competition law, it resulted in gradual judge-made legal innovation. It also generated new knowledge about the shortcomings of the ex post approach of EU competition law when applying it to the digital platform economy. As a consequence, secondly, the introduction of the Digital Markets Act (DMA) (2020 onwards) as a radical statutory innovation is discussed. The DMA introduced a novel ex ante regulation for large online platforms to overcome the problems of traditional EU competition law. Finally, the paper reflects on the impact of wealth effects and the (co-evolving) cognitive constructs of the relevant players as drivers in this current example of the co-evolution of law and technology. The paper concludes with an outlook on further areas of empirical and conceptual research that can provide a better understanding of the co-evolution of law and technology and allow for better policies in regard to disruptive technological innovation.