How come you switched topic part way through?
Also it is possible some sites are selling others' stagnant btc if its been dormant there for a while. I think we might see a problem like that coming at some point or just random accounts being ablitorated for no reason once they get to a certain age. You're probabky better off storing everything far away from anyone else's control.
if the exchngers fall the crypto will fall.
exchngers are center point of crypto.
on the excngers the btc price is dictated and everybody all around the world follow this.
exchngers are the main thing in crypto dont say that excngers cant be trusted if not then its bad for all crypto !!