In 2018, when Bitcoin was trading around $4,000 and most Americans, at least, thought cryptocurrency was a fad, Katie Haun found herself on a debate stage in Mexico City opposite Paul Krugman, the Nobel Prize-winning economist. As Krugman focused on Bitcoin’s wild price swings, Haun steered the conversation toward something else — stablecoins. “Stablecoins are really interesting and really important to this ecosystem to hedge against that volatility,” she argued on stage, explaining how digital ...