Overtourism presents significant challenges to popular tourist destinations, necessitating innovative approaches for effective visitor management. This study explores the application of digital nudges, specifically the decoy effect, within recommender systems as a strategy to mitigate overtourism. By conducting focus group experiments, we assess the impact of the decoy effect on the spatial and temporal steering of visitors. The findings indicate a stronger preference for spatial steering, where introducing a decoy option effectively redirects tourists to less crowded destinations. Additionally, the research highlights the complexity of visitor decision-making, revealing that personal preferences and prior experiences often influence choices more than digital interventions alone. These results underscore the potential of strategically designed digital tools, such as recommender systems, to promote sustainable tourism by balancing visitor distribution. The study advocates for further exploration of tailored, technologically driven solutions that account for the diverse motivations and preferences of tourists, aiming to alleviate the pressures of overtourism while enhancing the visitor experience.