"A business corporation is organized and carried on primarily for the profit of the share-holders. The powers of the directors are to be employed for that end. We are not, however, persuaded that we should interfere with the proposed expansion of the Ford Motor Company. In view of the fact that the selling price of products may be increased at any time, the ultimate results of the larger business cannot be certainly estimated. The judges are not business experts."
Yes, they are primarily in it to make money for their shareholders. However, it's nearly impossible to tell the effects of many decisions on the company's bottom line, and moves that increase the company's image in the eyes of the general populace can certainly be argued to have effects that increase the financial well-being of the company.
There's something called the business judgment rule that's applied in cases such as this. The board members must act in good faith, act in the best interests of the corporation, act on an informed basis, not be wasteful, and not involve self-interest. This gives a great deal of wiggle room because, as the judge said in Dodge v. Ford Motor Co., "judges are not business experts."
A move like eschewing moves away from net neutrality is arguably (which is all it needs to be) a move done in good faith to increase the bottom line of the company, especially since it builds goodwill with consumers.