[martin8412]

"No, because the point is that you get to know who sold them the RAM chips that went into the device, because the RAM chip vendor digitally signed the sale of those chips to them, and their repair job "consumes" that item in their own digital inventory to convert one manifest (representing all the parts in a phone with bad RAM) into another manifest (representing all the parts in a phone with good RAM.) The provenance of the replaced RAM chips "travels within" the provenance of the repaired phone. It's a tree of component sourcing, not just a log of repairs."

Which they only do if they are already trustworthy. I don't trust them. At any point in the chain, a vendor/manufacturer can put whatever garbage they want on the chain because the chain can't interact with the real world, and for that reason, blockchain solves absolutely nothing in the space of supply-chain management.