Man, my condolences for losing your friend. It's true that death is uncertain, and all of us have to taste it sooner or later, and we never know when that is going to be, so it's always better to be prepared. Those of us who have religious beliefs tend to believe that we need to prepare for the final examination by doing good deeds when we are alive, earning as much virtue as possible, because we can only have a better place in the next chapter if we do so.
Talking about Bitcoin investments, you're right that those who have reasonable savings in Bitcoin should look for a way to let their loved ones know about their holdings in case of an unexpected demise. I believe one should at least have one person in their life that they could believe with anything, so that they can let them know about these things.