As the backbone of the open science campaign, open science infrastructures (OSIs) play an increasingly important role in scientific innovation and the digital transformation of society. Nevertheless, OSIs still have a range of issues to contend with, particularly as they move towards more openness and a sustainable future. In this paper, as a case study of OSIs in China, we present the experience of operating CloudRT—the first and only open-access cloud-native high-performance computing ray-tracing platform in the world. Quantitative analysis demonstrates how such an OSI can produce an interdisciplinary impact beyond expectations. Moreover, the value of CloudRT is also shown through its acknowledgement by participants across the whole innovation chain, from pure science and engineering to applications in vertical industries. Both inspirations from this practice and its open challenges are discussed. Suggestions are put forward to guide the future efforts of stakeholders to develop a fruitful OSI ecosystem.