I don't believe in such predictors and I suggest you to not blindly follow any such predictions either. Look the predictions made are based on either analysis or hype and I can tell you easily that when you yourself analyze the market, you make predictions and speculation based on some facts and market data while if you rely on others doing it for you, it might be purely based on hype.

That's a myth, there's no one ever who can know the market movement in advance unless they are a whale who knows how to manipulate the market or is part of such groups who manipulate the market.

How do these predictions affect the market? The same as Elon Musk's tweets, they do nothing but create a particular sentiment in our mind which then affects the market as they want.