Dead on.
During the Iran-contra debacle I bought a large scanning, trainable satellite dish (this was just before scrambling became common, then universal) with some good ICOM equipment and started finding and watching as many of the raw feeds as I could from all the news agencies and networks. It was truly incredible to watch the first feeds of the day, which then went to the central office in one form, only to hit the distribution feeds in another form- after the first re-write- (sometimes rather mild), and then, as the day wore on, get progressively massaged. To see the "acceptable" spin applied by the prime time news was very revealing.  Like--a different story entirely, often.

Intrusions of the unanointed, unwashed into the real data stream (like mine)was one of the reasons for the huge pressure to encrypt.

So, as you point out, this perverse propaganda process is far from new- in fact, it has long been a basic element in "news" distribution.
But we are far, far better at lying to ourselves than the USSR at it's peak ever was.

We believe our own bullshit. They didn't.

Capitalism searches out the darkest corners of human potential, and mainlines them.