Elon Musk is a high-profile individual so his words can impact everything.

But NO, he's not manipulating the market because after all, why should he? His tweet is based on his view and people are riding it. If there's manipulation, he can move his coins but there's nothing such as that, and what he's just doing is making some shill tweets.

Investors are not dumb. Since Elon creates hype, they know for sure that there will be a time that he will also do another way around and some investors take advantage of that.