In all honesty, this is an inspired argument to pursue. Pursuit of truth (or at least "veracity") is effectively their fiduciary duty. While I doubt there's a legal claim, as tabloids aren't so limited; there may be a valid social accusation of fraud. At the least, its an exceptionally good point of messaging that most people would instantly comprehend.
One more point. Its becoming clear how effective this platform is becoming at leading the narrative. News platforms and companies are increasingly terrified of losing the audience, resorting to mining here and similar platforms for stories and rebuttals. If the definition of duty is validly and defensibly attacked from here, and further marginalized on their side; it will deal a significant blow to the MSM status quo. Many current and former journalists are already asking the same question…might just need a little firmer push.