It doesn't mean what Elon Musk said is true right away. Let's just remember that he is a businessman so when he knows he will benefit, he will definitely do everything for it. And from what I've seen of Musk, he hasn't wanted anything that he hasn't gotten, he's that kind of businessman.
So at this point that we are talking about, this may be just one of his strategies so that when people find out that he is investing in something like this, he will take steps to get people to hype him up again that he will follow for sure what he says if which coins to buy actually.