Musk has had positive things to say in the past as well, such as this tweet calling cryptocurrency brilliant where he also predicted the end of money as we know it. 

But it hasn't been all good, scammers posing as him doing fake Ethereum giveaways once got under his skin, but he directed his anger at Twitter for taking too long to ban the imposers.

While he's never had a bad thing to say about crypto, he still maintains that he does not own any.  Although I've heard many people say they're skeptical, finding it hard to believe because he seems to have done his research, sees it's potential, but hasn't bought at least a little.