Why is Vanguard controversial?

Can you elaborate on the reasons behind Vanguard's controversial status? Are there specific issues or practices that have sparked criticism and debate within the financial industry and among investors? How does Vanguard's approach to investing and asset management differ from that of other firms, and what impact has this had on its reputation and public perception? Additionally, have there been any notable incidents or scandals involving Vanguard that have contributed to its controversial status?