There are a couple misunderstandings here.
- No serious proposal for fighting fake news involves filtering. Facebook’s proposal involves manipulating ranking (so that spurious articles, which have until lately had an artificially high ranking, will appear lower in the newsfeed than similar real articles) and tagging articles visibly as suspicious, along with an extra dialog when sharing. Likewise, extensions for identifying fake news rely upon tagging. The point is to ensure that people are aware, when sharing an article, that the article they are sharing is from a systematically unreliable source; given the number of people who react with horror to Onion articles, this kind of clear tagging is probably justifiable even on the grounds that obvious satire is not obvious to drunks.
- Satire and detournment will always have a place in discourse. However, they function via an interplay with a consensus reality. The problem with “fake news” is a collusion between large groups of people to create an internally consistent but false version of world events, in order to manipulate people who accept it into performing specific kinds of actions. Presenting a collage of Hitler and Moussolini kissing is very different from creating a media ecosystem of hundreds of sites all geared toward selling people on the idea of drinking colloidal silver, or replacing all their money with gold bullion, or shooting up pizza parlors; for one thing, while the former is easily fact-checked, the latter can only be fact-checked by referring to sources outside of this alternate media universe, which of course are tainted in the eyes of those taken in.
Art can be very powerful. As a result, we should use it responsibly. If people are dying because of your artwork, then you bear some responsibility for their deaths; likewise, if your artwork led to suffering, the onus is on you. I won’t say that fake news stories can’t be art; I will, however, say that politically charged art doesn’t exist in some pure apolitical universe without consequences.
If you can’t act responsibly, someone else will take responsibility and recontextualize your art in a way that you may not like; if your community can’t police its own behaviors, then the people your community effects will police them for you.