I would have preferred it if you limit the scope of this topic to cryptocurrency and not the entire digital currency as Bitcoin can't take the place of many digital currencies it met to the point of becoming dependent on it. But for cryptocurrencies, I doubt if any of them would still survive if Bitcoin fails.

This is why I would have loved it if your topic of the kidney could be changed to that of the heart since the heart is one and the kidney is two. You can survive with one kidney. This makes the heart more important.