Nothing indeed is impossible; anything can happen. We can also wake up one day and notice meeting the unexpected, but like you have already noted, such a thing happening—I mean, the market crashing to zero—is very slim, but let's assume it does happen. Then everything that revolves around it will lose its value, and the entire crypto market will crash with it as well before people can start picking up its pieces. And will people lose hope on decentralization? I don't know, but until then, people will be more focused on what they have lost than on thinking about replacing what just collapsed.