RE: Why "I like blockchains, but not cryptocurrency" is ignorant.
I like what Ari Paul said about permissioned blockchains last year:
Yes - I think that banking, medical, and supply chain industries will be "transformed" by permissioned blockchains, but not because permissioned blockchains are new or interesting.
Rather - these industries simply never implemented other types of permissioned distributed ledgers that have been around for 50+ years. So now all of the focus on blockchain is pressuring them to finally upgrade their databases that are comically obsolete.
https://twitter.com/AriDavidPaul/status/983104467762536448
When you look at markets and supply chains, some are obviously better organized than others. When blockchain proposals are popular, that suggests a market failure - which could be solved by a centralized solution if there's an organization trusted by all participants.