That first paragraph really nails the problem.
It's already a massive bubble. When voices are narrowed even further, it grows increasingly out of step.
Our national media have long been something of a NY-DC circle jerk where they all just talk to each other, report on each other, stroke each other for access and exposure. Whenever they do stories on other parts of America, it always takes on this kind of Gorillas in the Mist filter. It feels like David Attenborough should be narrating anything that takes place outside of a major city. "And here we see the hourly worker clock in to the Serengeti . . ."
I think, worst of all, bubbles make people more partisan. They're just talking to and reinforcing each other all day. "We believe this, right? We can't possibly be wrong. Ok, it's everyone else who is stupid and wrong." People no longer have conversations. They have slap fights, mob up to get people they don't like fired, and seek heretics whose pixels they can burn at the digital stake.
This is seriously socially toxic behavior. That our media and academic classes are some of the most vigorous participants should disturb everyone. We are becoming even dumber as people. Whenever the Right starts going on about "the elite" I always think, "What elite? Have you seen what these people say all day? It's 50% illogical gibberish, 50% pandering for likes and retweets."
I read Twitter mainly for pop culture content I enjoy. Going there to read about politics is pure poison. Social media are half the reason people are watching the Ukraine war like it's a new Netflix series where they agitate for the writers to start World War 3 for an enjoyable season finale.
There is little basis in reality to any of it.