I can really only see three solutions:
1. We just buy everything direct from the supplier. Companies like amazon manage distribution. 2. We provide tools to allow the consumer to track the supply chain process. Products shipped with unique QR code, printed at the of manufacture? Users able to verify that this product was actually manufactured by the stated supplier. Could be an interesting startup idea? 3. Consumers get better at evaluating products on their own merits. Verifying battery capacity, performance etc.
3 is basically what you have to do if you purchase anything in Shenzhen markets. You can't just trust a particular supplier, or even that one batch has the same performance characteristics as the last.