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.
No, the real reason why people follow him because he is the CEO of the Tesla and is one of the richest person in the world. Secondly he has been tweeting about bitcoin and doge coin recently which is causing the crypto market to pump. That's the major reason that these days many crypto currencies traders also follow him on twitter.