On the national level, there are multiple sources of news (NYT/News Corp/Disney/Comcast/Paramount/WaPo/LATimes/etc). There are lots of sources of professionally and amateur produced entertainment. Apple/Amazon/Comcast/Disney/Sony/WarnerBrosDiscovery/Paramount/etc.
If anything, the monopoly exists on wired broadband to peoples homes, which is usually only available from one seller.
NYT - billionaire Sulzberger family
WaPo - Jeff Bezos
LA Times - billionaire Patrick Soon-Shiong
Disney/Comcast/Paramount represent the consolidation of an industry that used to be hundreds of independent newsrooms into a dozen or so corporations. The murdoch family's New Corp is regularly analyzed as a political force on par with individual elected leaders, if not more so.
Entertainment: Apple/Amazon/Comcast/Disney/Sony/WarnerBrosDiscovery/Paramount
The problem is that the industry has consolidated into a number of players you can count on one hand.
We can go through business by business and see the rise of monopolies and oligopolies. Universal owns half of the US music market - Universal, Sony and Warner own over 80% of the US music market. Accounting is done by the Big Four, advertising by its own Big Four.
Just down the line - consolidation, oligopoly, monopoly. That is what markets produce. Standard Oil reversed its breakup into ExxonMobil, as did the Baby Bells into Verizon and AT&T. Even the government intervention into the monopolies gets reversed.