These mutual funds and ETFs actively participate in corporate governance, and the overlapping ownership of most stocks in the market is a very underrated problem.
Economists have found evidence that as ownership concentration increases, firms act more like a monopoly.
Economists have found evidence that as ownership concentration increases, firms act more like a monopoly.
See this paper for one example in the airline industry: https://onlinelibrary.wiley.com/doi/full/10.1111/jofi.12698