Blockchains solve one piece of a puzzle I can trust the transaction to go through but I can't trust the ecosystem that it operates in -- I'll leave the definition of trust purposely ambiguous. Despite all their flaws the systems already in place are designed with the ideal to prevent anti-social malfeasance. No sane business will adopt a blockchain for a problem that already can be solved using cheaper methods -- you don't need to embed certain controls in technology, you can simply catch stuff using manual human powered processes at a much lower cost which are much more flexible than a program. Cryptocurrencies make it easy to pay any address I know exists and they also let someone purchase illegal goods easily.