Let’s be clear. A PoR wouldn’t have “stopped” FTX, Quadriga, or Mt Gox. All three were insolvent for long periods of time, due to either fraud or hacks. But in a world where PoR is normalized, their refusal or inability to perform a PoR would have stuck out like a sore thumb, and alerted users that something was likely awry. So PoR, at the industry scale, works via negativa – it’s most telling if you don’t do it.