Why should I think this man has special insight into the state of the world? He is quite rich, that is true. But if anything, by definition that means he is deeply out of touch with the needs, desires, and problems of the vast majority of the people on this planet.
Because he’s self made. He got rich precisely by being in touch with the needs, desires, and problems of people. And also by being successful at investing, which also requires ability to read trends etc. Would you also argue Warren Buffet (literally nicknamed oracle of Omaha) has no special insight because he’s rich?
Warren Buffet has insight on what it's like to be rich, and insights on how to win at capitalism. That does not qualify him to speak about progress in general. Peter Thiel may be good at reading what trends will make him money, but I don't believe that makes him qualified to say what would make the world better (i.e. progress).