Open-source software (OSS) forms the backbone of industrial data workflows and enterprise systems, yet many OSS projects face operational risks due to informal or centralized governance. This paper presents an industry-relevant case study of data.table, a high-performance R package widely adopted in production analytics pipelines, which underwent a community-led governance reform to address scalability and sustainability concerns. Before the reform, data.table faced a growing backlog of unresolved issues and pull requests, unclear contributor pathways, and bottlenecks caused by reliance on a single core maintainer. In response, the community initiated an open redesign of its governance structure. We evaluate the impact of this transition through a mixed-methods approach, combining a contributor survey (n=23) with mining project repository data. Our results show that following the reform, the project experienced a 200% increase in new contributor recruitment, a drop in pull request resolution time from over 700 days to under a week, and a 3x increase in contributor retention. Community sentiment improved around transparency, onboarding, and project momentum, though concerns around fairness and conflict resolution remain. This case provides practical guidance for maintainers, companies, and foundations seeking to professionalize OSS governance. We argue that well-designed governance is a critical enabler of industrial OSS reliability and developer engagement, supporting the long-term resilience of software supply chains.