It sounds like she did "reveal" some secrets about the company and how they use algorithms to manipulate emotions, not just as a byproduct but as a direct purpose of the algorithm. But we kinda already knew this, especially from the Netflix documentary.

I think the ploy here is that the whistleblower "admitted"/"revealed" some things we already knew so that Facebook could control the blowback and use the whistleblower to manipulate the story into something they prefer.

Facebook was already inevitably going to take a hit. Eventually someone was going to say "Yes, that Netflix doc is real. Yes, they're manipulating your kids. Yes, they experimented on how depressed they can make you. Yes, they're censoring anyone who's even slightly right wing. Yes, they're controlling your ability to find actual news information. Yes, they're injecting their opinion into the things in the name of fact checks." Instead, they manufacture the situation to something they can control. So, they still take the hit on the first half, but the second half turns into "Yes, they don't enough to censor right wingers. Yes, they still have information slip through the cracks of the fact checkers."

So, the result is that the public is mad at facebook, as they always would have been, but now the public demand is for the exact thing facebook wanted in the first place: more control.