It's because they want to manipulate the market of cryptocurrency, they will say bad things about it to create fear to small investors and of course people will react and panic because those people who said those things have influence. I'm sure they don't want the price of Bitcoin to surpass the $10000 mark yet so that they can buy at the bottom. They will not agree to be interviewed and ask about Bitcoin/cryptocurrency just because they want to say their opinions, I'm sure there's a hidden agenda and that is to manipulate the price. I remember when Bill Gates said that Bitcoin is better than currency few years ago while the price is not that high, now that Bitcoin price went up he's now on the other side, lol.