This critique of Bitcoin is quite short, and seems directed at Bitcoin in particular, in no way do I conclude that he is against the concepts of blockchain (say non-currency), or perhaps even cryptocurrencies that do not take on some of the Ponzi aspects.
After reading this I can perfectly imagine (but do not claim so) that he might support certain other forms of blockchains and/or cryptocurrency...
Here's his primary English writing on Bitcoin and cryptocurrency in general (not necessarily blockchain), sent to the SEC: https://www.sec.gov/comments/sr-batsbzx-2016-30/batsbzx20163...