I will say this: it is difficult for us to imagine what tasks and problems will be faced by a person in 20-50 years. And maybe we even will not even consider the problem. After all, if my grandmother knew all this, she would say that we are crazy.
Your grandmother just does not know what blockchane is. Try to explain to anyone the realties of friends, relatives, what kind of technology is it, or will they consider you a fool? or do not attach importance, just another technology.