Then it would be an opportunity to create the next Bitcoin, but a lot of people will be afraid to invest due to the fear of it disappearing again, for absolutely no reason.
That would be the real case scenario, to be honest. People would never use or support crypto currency at that time after what happened. Though we all know that it will not happen since no one can make crypto currencies "vanish". As no one controls it, no one would be able to do that, another thing is that each bitcoin wallet is an access to a part of bitcoin, for example, so as long as you can access your wallet, it will not vanish.