The shareholders of Twitter generally have 99.9% of their assets in other companies.

Therefore their interest in profits doesn't necessarily translate to an interest in Twitter profits. Even with the most abstract theoretical profit-maximizer model, damaging 99.9% of your investments in favor of 0.1% is not how an entity would act.

This is generally a good thing, but it's also what people are complaining about with the board of directors.

If shareholders and directors are not diversified, then they can make a lot of money through destroying democracy, poisoning rivers, whatever, and then escape to New Zealand or somewhere. You know, "externalities". Monopoly-guy in a top hat.

But if they are diversified, then the profits are not worth it to them, because many of the externalities are now internalized.