When the internet was young and I was wide eyed optimistic I thought reviews and ratings would solve this problem. It didn't. Then amazon came along and promise

When the internet was young and I was wide eyed optimistic I thought reviews and ratings would solve this problem. It didn't. Then amazon came along and promised a similar panacea, user ratings... but again it didn't quite happen. I feel twitter suffers the same problems. Who is genuine? Who has unbiased knowledge? Who can tell me the truth about a product? Can I know your credentials online without knowing your name? ((Imagine twitter posts being flagged "This person has no qualifications and has failed a basic maths exam")) -- idea - online exams with my results cryptographically signed. Block-chain seemed to offer some sort of solution. Maybe if we had trusted manufacturers of components, then these components could be tracked (along with pollution, carbon miles, labour policies, etc) all logged in the block chain. A bit like "fair trade" but for other items. Easily checked using your phone/bar-code before purchasing.