From the article:
The question is: Why in the world should he take a position on cryptocurrencies, even in the public debate? The answer probably lies in the pressure that traditional banks, hedge funds and investment companies like his are feeling from their shareholders. Those shareholders are seeing others get 1000 percent returns or higher while they are forced to make do with typically low single-digit results. The leaders of these companies need a response to the pressure and have to justify why they shy away from Bitcoin, Ethereum and top technology tokens in Initial Coin Offerings. They sound shrill in the face of an avalanche of evidence that they have missed out on huge gains.
I certainly believe this is a factor, but to my understanding, he doesn't really talk about cryptocurrencies unless asked about it. He's one of the more famous investors in the world, so I'm sure he gets this question a lot. If he really wanted to ruin crypto's image, he could have disparaged it without conceding that he doesn't know anything about it. What he's basically saying is it's his gut feel, given that Bitcoin is driven only by demand without any backing whatsoever.
I disagree with him, obviously, but I feel that people are making too big a deal out of his
admittedly uninformed opinions.
The article did make great points about him being anti-innovation though, so that could also explain his stand, and why he takes it despite not knowing about the subject.