I think the principle is let your family knows the private key and all your transactions before the death. The condition should be set long before the day of illness. Much pleasing to let your wife know your own business. Make sure she is not your enemy. Me, I will let my parents, and future wife know my wallet and private keys to avoid useless efforts.
Most often, death comes suddenly and most people do not have time to prepare for it. A person is arranged in such a way that he does not think about his own death, therefore, unfortunately, the cryptocurrency will be lost all the time. For a long time there was information that more than 6 million bitcoins were irretrievably lost. This is not only as a result of sudden deaths, but also as a result of mistakes, ignorance and other reasons.
I am faced with the fact that often wives do not show due interest in cryptocurrency, including because of their workload with the main things. Therefore, it is very difficult to dispose of cryptocurrency in case of death.