Being a shareholder is like being a voter. It’s more symbolic than meaningful. Companies of any size are affected either by a) threats to the brand perception by customers or b) threats at regulation. These two are more effectives strategies than minority share ownership.
IMHO there is a trending body of thought that suggests shareholders are not owners but speculative lenders. The recent Apple dividend distribution was caused by economists blogging and publicly decrying the company’s hoard. This caused the company to issue dividends defensively. And the powerlessness (and frankly, lack of utility) of shareholders was part of that discussion. Lynn Stout has written a book “The Shareholder Value Myth” and I think it accurately represents the mythology around shareholder ownership.
https://www.quora.com/In-the-US-is-it-realistic-to-try-to-achieve-labor-progressive-goals-in-businesses-through-more-active-shareholder-participation-rather-than-government-regulation