A large quantitative change is indistinguishable from a qualitative change: what's the difference between light rain and a flood, between some small waves and a tsunami?
What I meant, is that in the eyes/ears of those RECEIVING the information (and believing it uncritically), there's no difference. People have always had a predisposition to uncritically accepting information from those "in the tribe", whether that be extended family, or an internet echo chamber. Presumably this was a survival optimisation. Trust those "close", and distrust "others".