Remember all altcoins are pegged to centralized exchanges and bitcoin which are also pegged to fiat.so if bitcoin loses 90% of its value so do all altcoins because they have no exit. Warren buffett is no tech expert but hes predited a very bad ending for cryptos for the simple fact they have gone up to fast.All that being said steem iota bitshares EOS still have huge potential .can see bitcoin being pushed up to 30 k by the end of 2018 before the whole thing pops MY advice to anybody trading take some of the table here and there and look to invest big when the whole thing crashes