I think there is nothing we can do about it. Because everyone have many chances to access info about everything, including crypto. I think, its best to leave them alone with their own opinion.
just change the opinion about the crypt with different words and persuasion is hardly possible, but changing the way of life using the crypt in everyday life . this may lead to a change of opinion about the crypt.
I think its better for them to believe what they have think about crypto, because we have different perspection on how and what crypto is. The positive motivations will help some investor to lighten up their negative mind to contour and deliberate the coins in a positive way. As long as we are spreading positive fud then our duty is enough for them to trust crypto as the assurance fund.