RE: 6 media companies control over 90% of what we see and hear.
Hmmmm... who are they?
ABC, NBC, CBS.... who are the other 3?
NBC is owned by Comcast.
CBS is independent, but they have significant partnerships with the BBC and CNN. CBS used to have significant partnerships with ABC and NBC.
CNN is owned by ATT.
The Washington Post is owned by Amazon. The WaPo might be the most important print source for USA political news.
The New York Times is tied or a very close second to WaPo for domestic USA political news.
Carlos Slim, a Mexican billionaire, is the largest shareholder of NYT common stock.
However, the NYT has a second tier of stock owned by the founding families of newspaper, and the families have complete control over the selection of NYT executives.
Excluding CNN, those would be my Top Five choices.
I do not know what the sixth media company is.
For Hard Left propaganda, I would guess the PBS platform of news programs.
I am not sure if the PBS news platform has more viewers than Fox News, but Fox News definitely has way more viewers than CNN.
USA Today - owned by Gannett - is the most read USA newspaper. Obviously, they are very, very Left.