"blackmail is legal" is a pretty depressing take, but it does seem plausible.
If I had an affair with a celebrity, I can start a bidding war for my story between all the movies studios, television studios, and publishing houses. That's legal. If I invite the celebrity to bid, then I've committed a crime.
I've always found it hard to justify blackmail laws.
I think blackmail is obviously wrong as is sensationalism and appealing to base desires over informing people. i am not sure where laws should apply, but these appear to be important levers in the control of our society we should pay special attention to due to their ability to enable and empower the unscrupulous. If we dont have laws to govern these thing we must accept the responsibility of society to educate everyone to a high standard (as an independent thinker, more than a rule follower) to mitigate the severe risk in this area.
If you actually had a setup as you described, all of the news outlets would publish the facts of your story, without paying you anything, because facts aren’t protected by copyright. The only thing you could sell would be an exclusive interview.
When I said publishing house I meant book publishers like Penguin Random House. I don't know where news outlets come into it.
Whether the medium is a book or a newspaper or a website is legally immaterial. Thinking about the information as news is just useful because no one owns the facts, only their particular descriptions of them.