because they think it's safer to invest in gold / silver ...
older people do not advance their minds, investment in the world of crypto is very unfavorable, because the world of crypto is a new investment and is not promising ...
maybe that's why older people do not invest in crypto ...
You are right, they prefer to invest in gold because they are more safer about the price of gold that is not unstable and as time passes by value of gold increases unlike the price of crypto market. And gold is existing for more than a decade or a century now.