It's bad luck to sell all in crypto.
Modern economists prefer diversification of their own risk. It's mean that even if they put some money on things that will fail and their money will pass away - they still got something in the pocket.
I think it's wise to diversify your investment portfolio to hedge your funds from fails. But unlike real world in crypto currency world people usually invest in coins with similar features and often the coins with common features are based on one algo.
In the world of fiat if you want to hedge your funds you should invest in different financial instruments most of which are shares of companies from different spheres (communication, oil, airline, etc)