Point taken on private v. public. Perhaps evolution / natural selection is a better fit. We see it all the time in the government / defense sector. If your agency doesn't stay relevant, you'll disappear. And there's nothing high-level bureaucrats fear more than that.
Again, just because multiple organizations have the same motivations and therefore act in the same way does NOT mean they are part of a "coordinated international lie-festival" conspiracy in the same way that the hundreds of people who flock to a Chevy dealership for an employee pricing sale aren't part of some anti-foreign automaker conspiracy. They just all have the same motivation, and therefore take the same action on the issue.
Btw, I don't think the agencies are overhyping either. Heck, I hope it's the JOB of organizations charged with worldwide disease control TO be paranoid. I agree with others however that the media is recasting cautious statements and actions to create a ratings spike.