The Buquebus and Sea-Cat ferries (and the cuevas, etc.) are the incumbent. As I understand Christensen’s idea, a disruption is new, worse than the incumbent (for the incumbent's customers), cheaper, and adequate for some new customers. Without opining on whether Christensen’s ideas are accurate or valuable in any kind of predictive or analytic sense, I will say that Bitcoin in Argentina certainly seems like a textbook case.