Why do people keep saying BTC is dead?!
Because they don't know what they're talking about. Those people are just handing their bitcoins to someone else who deserves them more.
Because of them are poor in knowledge about bitcoin. Or maybe some are not really open minded unto it, or it can be one of their strategy to give panic to the community to sell their coins to make bitcoin value will downfall at once.
Those are the people who have made huge loss in the past by investing their bitcoins at wrong place and now they are blaming bitcoins for that and they are busy in spreading the negative news about bitcoins and trying to divert the minds of other people but I don't think it will work.