I think you would find that the book or two hour YouTube documentary “Manufacturing Consent” by Noam Chomsky provides compelling answers to your questions. I do understand it can be irritating to hear “watch this two hour doc” as a response to an internet comment, but it really is a master work on the subject. I haven’t seen it in a few years so I can’t do its arguments justice, but it completely changed my views on how media works. I have been meaning to watch it again though.

For a different take there is a YouTube series from “Crash Course” on “media literacy” that I suspect goes over this, but I haven’t gotten that far in the series yet.

And then there’s also Michael Parenti, another author who has written and has YouTube talks on the subject.

Either way I just want to say it’s not wild conspiracy theory. It is an established body of work people are talking about here.