Blockchain began with only a single implementation: Bitcoin. Now there are thousands of blockchains and hundreds of blockchain technologies. In such a crowded marketplace, it is only natural that the technology will begin to have more purpose-driven implementations. Many of the drawbacks of blockchain systems, such as the speed, ease of use, and so on, are easier to solve with a purpose-specific blockchain system.
We've already seen the beginnings of this. Steemit is a blockchain-based social network built from bitshares/graphene technology. It has a consensus algorithm based on witnesses and voting, and the whole operation is designed around hosting social and blogging content. While still having many of the features of a public blockchain, by being purpose specific, the Steem blockchain is better able to function in its desired ecosystem...