I think that having a bot say that the article is a copy even by marking it as a referral to the original would be useful to the community. It would be about as useful as discovering the original source of a trending news story.
Plus, I'm lazy. Out of the treding stories on the frontpage, they have quite a few copied articles where people say it's copied. I noticed that I just stop reading the content at that point and go for the next.
RE: AI to fight plagiarism?