Those two articles of yours are indeed consistent with the infantilization thesis. Info-siloing is one of the causes, although it might be difficult to tease out the natural way in which birds of a feather flock together. Globalization and the internet give us the potential to interact with other cultures, but that doesn't make us all cosmopolitan or multicultural. Most of us will prefer to relate with those with whom we agree, if only to avoid challenging our beliefs and practices. This is why Trump's narcissism is such a tremendous symbol of our age; he's only an extreme example of the broader narcissism implicit in infantilizing consumerism.
And memes do seem to reflect a dumbing-down of culture. Twitter does the same thing, oversimplifying ideas, as we confine ourselves to the slots made available by the prevailing technologies. The tech writer Jaron Lanier worries about that.
Mind you, I’ve noticed one potential upside of social media, which is that their immediacy makes it harder to lie. Of course, we can conceal ourselves by writing anonymously, but there’s a whole genre on YouTube which features the honest reactions of people, and these seem to take on a mystical significance. We’re so used to the professional liars and agnotologists (obfuscating doubt-casters), that we long for unambiguous signs of an ecstatic breakthrough from the bullshit.
For example, there’s this amazing guitarist who goes by the name “The Doo” who has over three million subscribers, so he’s world famous, and who makes videos where he pretends to be a novice in front of strangers on Omegle, and then blows them away with his virtuosity. We’re then treated to the change in facial expressions when it dawns on the stranger that he or she’s been taken for a fool and more importantly when they seem dumbstruck by a theophany. They just can’t believe such a masterful guitarist is playing right in front of them (over the internet).
How often do we see genuine emotional reactions in corporate news, for example? There’s scripted culture, as in politics, business, advertising, and so on, and then there’s a subculture all over the internet that features these honest reactions. It’s like the difference between official Roman religion and the Mystery cults.