I don't find it "chilling in all contexts" at all. Organizations very often set up a single channel for information distribution to avoid confusion arising from

I don't find it "chilling in all contexts" at all. Organizations very often set up a single channel for information distribution to avoid confusion arising from rumours, personal opinions and speculations. "Whatever gets posted at _____ should be treated as verified info, and everything else you hear as unverified" is very common during events such as natural disasters.