Disagree. YouTube recommends me a lot of videos about science, Linux, nerd stuff, certain kinds of politics... It's an entirely different feed for my wife with her interests matched. Also my 65 yo relatives read completely different news articles than the ones I read. Same with Instagram, TokTok and Telegram groups they're a member of. It's not a slightly more niche thing, it's a completely different perspective on the world and what's important.
10 years ago we all used to watch the same 8 'o clock news... It has completely changed.
And it's on an entire different level than 15 years ago when the choice was like 5 different newspapers with a slightly different political focus. You're right that echo chambers, tribalism and groups have always existed. But the internet did quite something and brought it to a whole next level. Mass media is close to dead and it's the recommendation algorithm of the tech companies who shape the perspectives of most of the people. Tailored to their filter bubble.
And with the 2 party system and the politicians not addressing the problems... I agree. I think that's one of the major problems. And the USA has pioneered being an echo chamber for the "western world". I'd agree that it happened way earlier and is more pronounced than in other parts of the world. And these aren't healthy or sustainable dynamics.
I read a few and saw a few movies that tell me otherwise... Discussing an hypothetical "perfect murder"... Detailing how they were murdered with a frozen icicle so there won't be any weapon or fingerprints left...
I mean those examples are a bit exaggerated. But there are pretty realistic stories. And I'd say the lines between story and guide aren't always that clear. That's part of the thrill. The good ones are kinda detailed enough to be both.
Same goes for historical records.
And I think if you grow up completely sheltered from evil and true life, you're bound to miss out, not to know aboud bad things. You won't have any understanding or defense against it and will get exploited. And you're missing half of the fun and intelligence that would otherwise be your potential. Also you can't keep kids from having to make their own decisions forever. At some point they need the tools and knowledge to decide for themselves.
I can recommend the sci-fi dystopia "The Giver" about that. (The sheltering part, not the murder mysteries.) But read the book, the movie isn't good at all. And read it while you're young, it's probably more suited for adolescents than for adults.