Why smart mobility alone does not ensure accessibility? Social, spatial, and digital dimensions of mobility as a service in island contexts

Mobility as a Service (MaaS) is increasingly promoted as a key component of smart and sustainable urban mobility; however, empirical evidence on its capacity to deliver socially accessible and satisfactory travel experiences remains limited, particularly in constrained and insular contexts. Addressing this gap, this study investigates the role of social accessibility in MaaS and its impact on user experience, focusing on airport-to-city mobility in the island context of Sardinia, Italy. The research adopts a quantitative multi-method approach, combining a questionnaire survey (N = 391) with Space Syntax analysis. The survey examines the association between perceived social accessibility, user experience and satisfaction, and perceived spatial accessibility through Pearson correlation and linear regression analyses. In parallel, syntactic segment analysis evaluates the topological accessibility of airport-to-city corridors in selected island urban systems. The results reveal that accessibility is not merely determined by the availability of services, but by the interaction between social inclusion, spatial configuration, economic affordability, digital integration, and temporal reliability. While public transport affordability and safety were generally perceived positively, fragmented digital platforms, inadequate pedestrian connections, and service unreliability during peak periods undermined overall user experience. These insights underscore that MaaS effectiveness depends as much on physical and institutional coherence as on technological innovation. By foregrounding accessibility as a multidimensional and lived experience, this study provides a grounded and actionable contribution to the development of more inclusive, resilient, and user-centred MaaS systems in island and peripheral contexts.