He's right, however, managers can simply say, "We believe long term wealth maximization is dependent on not being assholes and getting the company regulated out of existence," and that will be the end of any shareholder lawsuit on the subject. US case law gives wide leeway to managers to determine what is best for the business.
99% of the time, that doesn't actually happen, and even when it does, it tends to amount to more of an annoyance than a serious threat. It's not like it takes the CEO's time personally to deal with an activist shareholder lawsuit. They hire a team to handle it, and things move on.
Managers are practical people. They don't optimize for rare activist shareholder cases.