Bear in mind that "extremism" is the expected result of any reasonable algorithm that you abuse like this. If you like X, the algorithm will focus around X. If you like everything the algorithm suggests, you'll end up liking a "bigger target", and it will start suggesting stuff yet further away from your original starting point, until eventually you've "liked" everything. This is deliberately engineering a scenario in which Facebook will feed one a set of things that all seem "extreme" on some metric or other, be it "political", "pop culture insipid", or anything else, because they are all "extremely" far away from your starting point.
You are also engineering a scenario in which you are receiving "everything", so you will end up experiencing this proportional to raw volume within the segments of the interest graph that you've transitively explored. We can't eliminate the possibility that he's missing large chunks of the graph in his transitive exploration. A massive anime fan or somebody else big into niches and staying away from politics who starts doing this may end up with a very different experience. (In fact I'd suspect that it's decent odds that why the author ended up with "extreme politics" in the first place is that he probably had a pre-existing politics seed set of likes, which then "fuzzed" into the full set of political views while not getting into niches like anime or figurine collection.)
As a story it's interesting, but I'm not sure it reveals stuff about society so much as it reveals a very fuzzy picture of the author.
Facebook is supposed to be this big brother that knows everything you like, knows your whole circle of friend and acquaintance even maybe your inner thoughts. But in reality, it will forget everything if you have one day out of the ordinary.
Very quickly, the monetization model that Facebook uses is basically taking over the social aspect of the website. If you like it, chances are Twitter or even Reddit will give you a much better experience. That's a bit like if Google decided that you like ads so much you only want to see that and not the search result anymore. That's certainly something that Facebook investors should look at.
Lowbrow celeb culture trash and political extremism was selling newspapers for decades before the internet.
If there's anything interesting it's the proportion of content political extremist organizations are sharing to win "likes" from relatively sane people that actually isn't political extremism, or even vaguely related to their agenda.
The expected outcome of liking everything the algorithm suggests indiscriminately should be more moderation, not more extremism. If (as a oversimplified example) you like colors so the algorithm asked if you like, blue, green, yellow or red and you select them all, one would not expect it to eventually lead to a community that believes green is the best color and all others should be destroyed.
Your phrasing suggests that you misunderstood my point, but does not prove it. My point is not that he started with extreme politics (or politics that might be viewed as extreme by most people since of course $MY_VIEWS are always perfectly sensible and obviously correct, it's everybody else who is extreme), my point is that he started with politics at all.
"The expected outcome of liking everything the algorithm suggests indiscriminately should be more moderation, not more extremism."
Uh, no, that makes no sense. You're engaging in an operation that is deliberately blurring Facebook's impression of you. Open your favorite image editor. Cover an image with pure white. Put a blob of black in the middle. Start using the "blur" tool. It doesn't shrink. And that's not perfect, either... the center of the blob will remain the darkest, but in this system, Facebook keeps presenting you with more "extreme" views, and you keep telling it you like it. Of course it pulls you away from the "center"... you keep telling it to. And this is where the raw volume point comes in... the extremes are louder, so if you blur like that you'll see a lot more of it.
Similarly, purely out of chance you might be given the opportunity to like the "destroy non-green" community before the "destroy non-blue" community.
Maybe what we can take from the fact that the writer ended up shown/liking both left and right views is that the algorithm doesn't give a very strong weighting to negative correlation; i.e. even though people who like left-wing pages (presumedly) don't like as many right-wing pages; facebook still gives users the opportunity to like both. And possibly will not necessarily bias on one side of apparently conflicting interests when choosing what to present in the news feed.
Facebook has the advantage over a supermarket that they can sell you extreme political material without pissing off their other customers. What you end up with is probably what supermarket tabloid shelves would look like if people only saw what was tailored to them.
Actually, that does not sound surprising at all.
" By the end of day one, I noticed that on mobile, my feed was almost completely devoid of human content. I was only presented with the chance to like stories from various websites, and various other ads. Yet on the desktop—while it’s still mostly branded content—I continue to see things from my friends. On that little bitty screen, where real-estate is so valuable, Facebook’s robots decided that the way to keep my attention is by hiding the people and only showing me the stuff that other machines have pumped out. Weird. "
Maybe its more likely that its a reflection of those who have the power and influence to game the Facebook algorithm; i.e. those who are most heavily invested in the need/right to influence social perception. The right-wing are currently invested in this business with much to lose. Why is it such a surprise?