There's a lot behind this and I don't want to come off as if I'm pinning it all on a younger generation or [current fad] but it seems to have reached its peak to this point with the anti-intellectual tropes of "it ain't that deep bro" and "sometimes the curtains are just blue."
This is the culmination of a ton of factors in the west, especially the US, where decades upon decades of underfunding of education has finally had a cumulative effect a lot like deindustrialization. I know that sounds ridiculous but hear me out. For a long time as the US outsourced manufacturing, there was a skeleton structure of holdover manufacturing and logistics that kept things ticking over. Not like in the previous eras but enough that the problems as a consequence of deindustrialization didn't manifest until later. It's only as the last vestiges really fell away that it became apparent with the covid outbreak and the block in the Panama canal and soon after, the block in the Suez canal to a lesser extent (for the US) that it was obvious how bad things got. (That's when there was the knee jerk CHIPs act under Trump to try and reshore semiconductor fabrication, but that's a story for another time.) Anyway, a similar thing has happened with education and media literacy - there's a genuine literacy crisis in the US that forms the backdrop of the media literacy crisis but both of these have been coming down the pipeline for decades. As education outcomes dropped, older people could kinda keep things ticking over and they could impart a degree of literacy in all modes just by encouraging it and setting a higher standard, and workplace expectations also set the bar to a certain extent. This has gradually slipped away though. These days it's getting so bad that online people are getting AI to summarize content or a comment, then getting AI to generate a response, copy-pasting that, and then the next person responds by using AI to interpret and respond. This is because for some people their literacy muscles (literacy literacy or media literacy) are so underdeveloped or so atrophied that they aren't able to engage properly and they need a crutch to lean on. It's not all AI though, that's just a symptom of the literacy crisis.
This is also where a lot of vibes-based analysis comes in too. People struggle to actually advance a thesis and, when they state a position, it often lacks anything to back it up and if the person gets pressed on it usually their argument crumbles like wet cardboard. You see this with people throwing out weird allusions where they just rely on a "thing bad" response. One example that comes to mind is that I criticized Mamdani for being a Zionist online. A person responded that he absolutely was not one. I explained that he openly supports the existence of modern-day Israel as a state given he advocates for a two-state solution and thus that makes him a Zionist categorically. The person rejected this argument reflexively but couldn't actually offer anything more than "nuh-uh." When I paraphrased Wikipedia and said that Zionism is advocating for the political project of an Israeli state and that Mamdani fits this definition to a tee, they couldn't respond. But it didn't feel right to them. They were wholly unable to engage with the discussion though and they couldn't actually manage to talk definitions or principles and they were unwilling for me to dogwalk them to the point.
There's also a sort of siege mentality amongst progressive libs. The conservative libs have been very anti-intellectual for a long time, longer than I've been alive, and the old guard of erudite conservative libs is long dead. As a whole they aren't able to engage with anything to significant depth. But in the Trump/Qanon era, the progressive libs have been rudderless and they've been unable to defend the gains in the culture war, let alone getting their shitty candidates elected, and amongst them I see this sort of Weimar Republic progressive flavor of latent terror at the awareness that they aren't able to fight back, let alone win. So they seem to have shut down and closed themselves off in response to the rise of (more extreme) reactionary politics. This siege mentality makes progressive libs incapable of engaging with literacy on any serious level. (Idk I'm not really doing my point justice here but hopefully it suffices, I'm tired.)
I also see a lot of people who can't manage to engage in hypotheticals or, at the risk of coming off as a debate pervert, thought experiments. People genuinely seem to struggle with following through the logical extension of an argument. There's a developmental milestone that comes to mind and I forget what it's called but if you tell a younger child "Imagine gravity is reversed, so things fall upwards instead of downwards. If I drop an apple, what happens to it?" and a younger person who hasn't reached that level of development can only use their experience as a reference and they can't hold a frame where they consider the implications of a scenario where the imaginary rules have their own outcomes so they will respond that the apple will fall down to the ground, whereas the older child has reached the developmental milestone where they can respond with the counterintuitive answer of upwards. I'm not trying to pathologize this phenomenon by implying that people like this have developmental delays but if you don't exercise engagement with these sorts of things, you lose your ability to deploy them. It's a thing where it can hem in a person's ability to engage in media literacy because if you argue that a character in media is basically a stand-in for Hitler, for example, people will respond with superficial rebuttals but when you defend your argument with "But there is no Germany in this story" they believe it vindicates their rejection of the argument instead of asking themselves what Hitler would look like in this fantasy setting where, instead of being a German in the 1930s, he is an elf in a high fantasy narrative - if you can't hold the frame that there are different "rules" to the reality of a narrative, if you can't engage in comparative analysis or symbolic analysis, if your whole engagement with the world is purely vibes-based then you're gonna have very poor media literacy.
So imo it's largely due to the education system buckling under decades of defunding as well as a political context where people are encouraged to be incurious coupled with technological crutches that make it easier to avoid engagement, but the tech aspect is very downstream of the cultural and political aspects (political including education policy here.)
