Well bitcoin is already worlwide phenomenal to all group of individuals there, I can tell as well that they know what bitcoin is but they don't know how bitvoin workfs, to be honest it's hard to teach old people about cryptocurrencies, they have all this stuff of beliefs and perspective in life how money works nowadays, most of them has an on principle of life, butits never been too late to have this kind of knowledge to them, not all old people are afraid of changes, just start a good conversation at first and explain to them clearly how this thing works. Bitcoin is a generation of digital currency, it might be hard at first but that's always gonna be it, when you're on it already it will be easy to introduce to all old people.