The Tokyo 2020 Olympics has taken “Unity and Diversity” as one of its main mottos - this, in times of global migration-led diversification of societies, also called superdiversity by Vertovec. Recent migration policy changes and rising social movements in diversity issues seem to showcase Japan as an open and cosmopolitan country for diversity. Indeed, while the intentions for hosting such mega-events have often given priority to the economic effects, expectations have recently risen to also leave social and cultural legacies behind. However, besides the motto of “Unity in Diversity” as a rather ubiquitous feature of the Olympics, not much appears to have changed - at least politically - beyond marketing and urban re-development. Based on recent developments of policy and public debates regarding diversity issues in Japan, this paper examines the measures (not) taken by governmental actors, but also explores how the LGBT* community and activists seized the opportunity provided by the Olympics and the global media attention to initiate a momentum for a social change in the local society. Reflecting on the different dimensions of diversity from a transnationalism and superdiversity perspective, I argue how the Olympics might have contributed sustainably to the new awareness for the factual societal diversification in Japan.