Sam Altman, the chief executive of OpenAI, says that technological revolutions are driven by more than just technology. They are also driven, he argues, by new ways of paying for them.“There is always a lot of focus on technological innovation. What really drives a lot of progress is when people also figure out how to innovate on the financial model,” he recently said at the site of a data center that OpenAI is building in Abilene, Texas.Over the last several years, Mr. Altman’s company has foun...