Technology has already fragmented the news media landscape, as is obvious when we consider the diversity of news sources compared to as little as 10 years ago, and the extremism of their views. Much of the discord in the West is due to average people immersing themselves in echo chambers, in which their biases and preexisting views can be echoed by some official-looking man talking to them from a spiffy-looking studio. The fragmentation happened in this cultural realm early on because the costs of setting up and running a "news" source are low: Current events information is a free commodity good, curating it and repackaging it into a consumable product for a particular audience can be largely done by low-paid interns and twentysomething journalists, and cheap 4K cameras and green screen technology allow anyone to set up a professional-looking "news HQ" in a garage.
The TV and film entertainment industries haven't been obliterated by these forces yet because the costs of making quality shows and movies remain quite high. That lends itself to centralized control and the dominance of a small number of rich studios. The limited number of players and their geographic concentration in Hollywood and New York allow them to maintain cultural cohesion and to make products that are thematically consistent. Think about how many major American movies are "liberal" and/or "politically correct" compared to the number that are "conservative" and/or "politically incorrect." The bias is clear.
Technology will eventually undermine this, and fragment the entertainment media industry in the same way it fragmented the news media industry. Better AI and CGI will allow ever-smaller teams of people to make quality films and TV shows at lower and lower cost, and the logical endpoint of the trend will be fully automated production of individually-tailored entertainment content at trivially cheap rates. The result will be even more tightly circumscribed and defined reality bubbles, where even the escapist entertainment products people indulge in are customized to reinforce their biases and make them feel that they're right. For example, imagine a pirated, altered version of Star Wars meant for misogynist men where the men are all in charge and Daisey Ridley is nude and submissive for most of the film. Technology would allow the edits to be done seamlessly, most people who watched this version would never bother watching the real, "liberal" version of the movies, and even Star Wars fans wouldn't be able to agree on "basic facts" anymore.
It gets worse. Think about what would happen if this were paired with mass technological unemployment--since no one would have jobs, boycotts and pressure on employers to fire people who made or indulged in extremist/highly unpopular entertainment content wouldn't do anything. If you find out your neighbor spends all day indulging in racist and sexist virtual fantasies and hanging out with like-minded people, what could you against him? You can't tell his boss because he doesn't have one. Publicly exposing him is pointless since he already only hangs out with people who are just like him. You can't egg his house or harass him because surveillance cameras and robots are everywhere, and you'd be recorded and possibly arrested.