This ethnographic study examines the transformation of Italian indie culture under platform capitalism, tracing how digital infrastructures have reconfigured the relationship between independence and mainstream commercial logic. Drawing on fieldwork with musicians, industry professionals, and audiences across Italy, it argues that the semantic and aesthetic coordinates of indie have shifted from oppositional autonomy to a stylised modality compatible with platform logics, where visibility and metric optimisation increasingly dictate artistic legitimacy through commercial imperatives and through the internalisation of platform-mediated evaluative frameworks. The Italian case, rooted in a tradition of politicised independence, reveals how local infrastructures and cultural histories mediate these global transformations. Synthesising grounded, abductive analysis with historical reconstruction, the study identifies three intertwined processes – mainstreamisation, semantic drift, and platform gravity – through which visibility metrics and sponsorship logics recalibrate artistic practice, legitimacy, and audience address, recognising that these dynamics interact with diverse cultural trajectories and do not operate as a uniform homogenising force. The emerging configurations still depend on established intermediaries, informal circuits, and human decision-making embedded in longstanding power structures, even as platform mediation intensifies the circulation and repetition of certain stylistic and organisational practices. To theorise these shifts, the article advances ‘poptimism’ as a structural condition. The analysis shows how this gravitational field is absorbed into existing professional sensibilities, where platform mentalities recur within industry judgements shaped by longstanding organisational logics.