Vanguard literally provides for investment in every security. All of them. Every single one. I currently own interest in every equity security available to a US investor by purchasing a single ETF. How is it that Vanguard (which is owned by its funds which in turn are owned by individual investors in those funds) would benefit from coercing literally every publicly traded company from transacting with every other non-publicly business? For instance, of what benefit is it to Vanguard to prevent Sysco from selling food to restaurants that are not publicly traded? Should Apple not sell phones and laptops to any non-publicly traded business? Should Amazon stop transacting with non-publicly traded companies? How does any of that work in my interest as an owner of Vanguard?

The shenanigans are thought to be around M&A and alternatives. A company like Vanguard can use market power to juice its more profitable products by depressing prices.