These days the courts give wide latitude to companies to offer virtually any plausible reason why superficially altruistic acts are in fact good long term for shareholder value. Anyone wanting to do what Ford did just needs to keep their mouth shut about the real reasons.
Interesting. Do you know any particular court cases?
My wikipedia link above in turn links to https://en.m.wikipedia.org/wiki/Shareholder_primacy, which says in the last paragraph: "The doctrine waned in later years."
This probably confirms what you say, but I'd be interested to learn about specific cases.