Seems to me that if he didn't believe in Bitcoin, he's simply leave it alone... like thousands of other stocks and bonds he's not interested in. But he seems to go out of his way to make disparaging remarks... which suggests a personal interest or axe to grind. That, alone, casts doubt on the objectivity of his commentary.

Cryptos aren't going away, just like the Internet didn't go away even though lots of so-called experts came out and stated that it would never gain acceptance beyond a limited group of nerds/developers and some academics. As you said, the genie is out of the bottle... look at Japan, look at Switzerland, Greece, Turkey and other places competing to become the most crypto-friendly. They would probably not be doing that if they were about to illegalize cryptos.