We can see these days that not all people know cryptocurrencies, if they do perhaps they have heard only about bitcoin, but without owning or having the experience of making any transactions.
Maybe altcoins will become popular within 3 years from now?
So far, I see no reason that alternative currencies would become popular. At the moment, I see only speculation in the market with various coins. I think that in the future they will be in a different form. For example, in the form of securities. And it will really be interesting.