It's probably not about the ICO's themself but about market situations. Most of the ICO's (at least the barely legit ones) stated clearly in their whitepapers that it's an extremely high risk investment. But during the period from december to february, because of the extremely bullish market, a lot of people ignored any kind of warning and overinvested, thinking it will never go down. It's probably unpossible to prevent something like this because with the market in similar conditions to december/january a lot of people will ignore anything written on the websites and just buy, it's like gambling: you can put signs stating that it may cause dependency but some people will became gambling addicted. With large investors like this case it may be possible to do better checks from the ICO companies but there always be some standard investors that may overinvest. In some countries small money in the western world may be big money, that's hard to "prevent" something.