How is ethereum relevant here? All that's needed is a hyperlink and a hash code for each claim/source mentioned in an article.
Regular people don't understand hash codes, a popular cryptocurrency (which Ethereum might be in future istm) would serve that purpose without people needing to be nerds to recognize it.
People don't want to spend time knowing how all that shit works, the same way they just want to be able to recognize authentic cash notes in a physical wallet without having to know anything about specie currency or financial economics.
> One approach I'd like to see for this is the use of ethereum-style smart contracts to validate documents
You need to find a new hammer.
That's just the first thing I thought of (I'm not invested in it in any way and down't have any ethercoin). I just mean some sort of publicly-acceptable authentication mechanism that's simple and federated.
That's the big problem: it's that easy to delegitimize something in the eyes of enough people that a competing narrative, regardless of its factual value, can be put in competition with it.
One approach I'd like to see for this is the use of ethereum-style smart contracts to validate documents (and that it should be as obvious and reliable as a creative commons icon) and collections of source material and the semantic graph that connects them to be public, so that it's much harder for people to dismiss it by attacking the summary node that merely describes the relationship between them (the 'news story'). Textual narratives are stories about relationships and chronologies, but stories can be invalidated by attacking the teller. What we need are public shareable metadata and a protocol for linking disparate pieces of metadata together.