I don't agree that future economy needs cryptos. Why would it need cryptos? Cryptos are the newest way how the money circulates in the current economy and the market, but they are only the mean that is used. Money will always be there, whether it's a dollar, gold or BTC or something new in the future. We do not need cryptos to keep it circulating. Blockchain on the other hand shows us a new brighter future how information is transferred and it is already being used in other industries. Blockchain will be used as a tool even if coins die.