Shareholders already know that companies don't have an obligation to maximize profits. Tim Cook among others has made this point forcefully fairly recently.
Shareholders make investment decisions based on their own opinions of which companies are most likely to generate the highest return over their preferred time span. That is not the same thing as believing in an obligation.
Shareholders make investment decisions based on their own opinions of which companies are most likely to generate the highest return over their preferred time span. That is not the same thing as believing in an obligation.