That's not my point, although I will add to your statement that mainstream media vets and verifies what they post online, provides context and balances their reports by giving a voice to both sides. Therefore it is a better source of information than Facebook.
Half of the posts in Facebook are posted by disinformation campaigns, much of which is generated by Putin's troll army and the rest by right wing propaganda sources funded by who knows? Are you aware of that Facebook gave Cambridge Analytica access to information on its users without their permission? It's just the tip of the iceberg. So, it's dumb to go to an unreliable source of information to get your information, especially when you've already been turned into a chip to be played in the Right Wing poker game.
https://www.nytimes.com/2018/03/19/technology/facebook-cambridge-analytica-explained.html
Facebook and Cambridge Analytica: What You Need to Know as Fallout Widens
Cambridge Analytica, a political data firm hired by President Trump’s 2016 election campaign, gained access to private information on more than 50 million Facebook users. The firm offered tools that could identify the personalities of American voters and influence their behavior.
I won't get on a commercial airliner if I weren't confident it was reliable. Same with the news. There are plenty of good, reliable sources of media. No need to get it from Facebook.