I quit FB years ago when I started feeling like something was off. It was once fun to see what my friends and family were up to. But, it turned into an irrational battleground of ideology of people who had never ever cared about ideology beforehand. Oldtime friends fighting and hating each other.
Recently, I created a new FB account to see what I was missing. Immediately, I was bombarded with videos of scantily clothed teenagers, crypto hawkers, videos that hinted at Human's darker side. The friends that were still active were exclusively peddling memes of extremism. That experiment didn't last long.
I'm currently avoiding every platform that algorithmically decides what content to show me (except YouTube which generally shows me content that's interesting and useful to me). It's a relief to my mental health. And, I realize how much of my day was wasted with content that had no use to me.
Can truthful content be radicalizing? I think so. Should we therefore censor true, radicalizing content, or decline to show it to users who express interest in it? What does it mean to live in a democracy if true but radicalizing information is verboten?
Let's take the example from the article, the Great Replacement conspiracy theory. It is true that the US is undergoing rapid demographic change. Should algorithms refuse to show content discussing that? It is true that some people and politicians favor this change for various reasons, ranging from in itself to for the second-order effects: eg., "we need more people in order to to fund our pensions", and some do not. If someone is interested in these changes, is it brainwashing to display this related content? It is true that various US and governmental policies either directly or have the effect of promoting demographic change, and theoretically other policies could be in place that would discourage the same. Does content related to this count as "radicalizing" content? For some people it could be! Is it wrong in a free society to allow platforms to promote content discussing that seems like should be a very important issue? Of course, as is usual whenever you have everyman involved, there will be tons of ludicrous cranks taking all the above facts and claiming the Illuminati or the Jews are behind it all, but as seen above the line is fuzzier than it seems at first, isn't it?
We live in an age where lots of content is radicalizing, because social anomie and atomization are huge problems. In the second half of the 19th century and the first half of the 20th century, the conditions of the industrial era also made the populace ripe for "radicalization" via socialism/communism/fascism, all of which led to both individual (murders, beatings, assassinations) and later mass violence. But banning bookstores from promoting Karl Marx would have done nothing to stop this. The underlying social problems were the issue, not the ideological manifestations of them. No socially and psychologically healthy person reads anything and decides to kill people. But in a society where the social fabric is fraying and masses of people live unfulfilled lives, something will "radicalize" some proportion of them and they will act out in violent ways. Tuning algorithms is just playing whack-a-mole. That's why you can go and look into these shooters and find the whole spectrum of modern beliefs has "radicalized" people into killing people. They're already a lit match looking for a cause.
Papers in the late 1700s and early 1800s were certainly full of virulent and violent rhetoric. "Yellow journalism" was coined later the same century, and it was common for people to get all their news only from the party rags. It's been my observation that people tend to think "good journalism" came with the era of broadcast media, where the state (in the US) was able to acquire a previously unprecedented level of control over media that everyone consumed. This created a bubble for some people that consumed mainly this media, especially as their social connections weakened, but stuff like the Fairness Doctrine did not entail actually displaying much in the way of really controversial views, which continued to propagate outside the channels of broadcast media. This was the echo chamber, and a lot of people are still in it; all it did was mandate that you receive the two anodyne approved opinions. It's just that today, rather than say, reflexive anticommunism, there are new sacred cows that cannot be questioned. This echo chamber is sustained not by anonymous Twitter posters and YouTube conspiracy cranks, but by the chattering and political classes generally, and they really, really hate contrary political values and are intent on using the worst examples to silence all.
But also concomitant with the reign of broadcast media was, for most people in the US, good times, both socially, psychologically, and financially. Nevertheless the leading edges of the current crises were present, and you had people like Ellul influencing the Unabomber.