Well, it does exist but it’s premise is twisted and unclear. Dodge v Ford established such a duty exists but over time (as discussed in the article you linked) it’s been interpreted as a duty to the long benefit of shareholders. Dodge v Ford hinges on the fact Ford stopped paying dividends to pay his workers and that it was an enrichment of the employees at the expense of the equity holder. That’s been twisted around but never fully dismissed or accepted. But you can see shareholder value lawsuits all the time. However it’s a common law civil duty, not like a financial manager fiduciary responsibility that can bear criminal teeth.