What cryptocurrency need is to back it up with something materialistic, but all the materialistic things are already the property of somebody. People don't believe in something they can't see with naked eyes and can't well can't sense with their 5 senses. I guess currency developers need to develop some new "matter" to back it up. Steem,sbd(although it's also a cryptocurrency) it is backed with tons of data. I think Steem/sbd will leave everything else behind someday and might even be accepted as mainstream money at some point in future.