People follow him because he is the biggest man in cryptocurrency What he says happens. Is one of the people and when he speaks it is clear and easy.
He is a successful man in cryptocurrency The coin he talks about gets his price up. a few days ago he tweeted about dogecoin and check his price where are you. I think that's why people follow Elon Musk.
An easy answer he is the richest man in the world that is why the world follows him. Once he says something about anything people think that he likes it and is getting into it so people simply follow him. On the other hand he is doing so much work on and for technology that people follow him.
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