My main concern with Peter Thiel praising monopolies is that the nuance of the message will get lost - "earning monopoly through radical innovation" - but the core message remains - monopoly = profit. People will start to pat themselves on the back for acquiring all their competitors, skewing regulations in their favor, and a variety of other sleazy business tactics. I suspect most large business CEOs already understand that monopoly = profits, so Thiel is just making it respectable to talk about by casting it in the light of innovation.