Now, whistleblowing against the government is always a dicier proposition, but that's certainly not the only definition of whistleblower.
If the whistleblower has too much backing, odds are also that the company is not particularly bad and the company's being targeted for other reasons. It's a type of shakedown: everyone in the Mafia is a criminal, but when one Mafia family becomes disfavored, the police magically get a full report of their crimes, crack down on it "because we need to get hard on crime", and the other families consolidate their power. Yeah, the disfavored family actually committed the crimes that they're suddenly being arrested for, but the overall effect of the crackdown is not a reduction in crime.
The "whistleblowers" reporting on Facebook are doing so because someone with a lot of influence wants them to. Maybe the government, maybe internal pro-censorship Facebook factions, maybe the press, maybe an actual outside rival. But the ultimate goal of whoever it is is more censorship, but of the proper type.
That is not a defining characteristic of a whistle-blower. It's sadly still a common consequence to take the risk of that, especially if you blow the whistle upon a state, which is not the case here.
But characteristic and common consequence are not the same thing at all.
What's with all the effort to discredit this source?
If you don't think FB would organize a pro-FB shill campaign, you haven't been paying attention.
The tell is the ad hominum "not a real whistleblower"/"has a PR team" (as if FB doesn't) attacks without any corresponding claims (much less any evidence) that the information is in any way incorrect.
Or failing that, one could make the comments such a shit-show that HN decides to flag the whole story off the front page, as is their right.
You'll have to make up your own mind as to if that's happening today and on other days, as specific accusations are frowned upon in the site terms (2)
1)
https://en.wikipedia.org/wiki/Doubt_Is_Their_Product
https://pluralistic.net/2021/06/10/flicc/
2)