That is a wake up call from the co founder of ETH, no one should invest his/her saving in cryptocurrencies and again invest only what you can afford to loose because the cryptocurrency market is very volatile and at that it is unpredictable any thing can happen but in at that taking the risk some times pays off.
Vitalik is telling the truth. And in fact, there are many coins that lose its values especially the cam ones. Remember bitconnect? Anytime, someone can dump the coins price, its a reality. But of course, until there is a supply, and when all is dump, theres nothing to drop anymore, but only for the coins to go up. As rule, Invest only the amount that you can afford to lose.