The article is written in a very straightforward manner, if these facts are in fact true. According to this alleged document.
This isn't an anonymous source. This is a leaked document from Twitter management. Presumably NYTimes can eventually release more details if pushed on this issue and offer more solid proof.
But "anonymous source" usually means "Dude who emails reporter", and often someone who is an executive level or above. You know, someone who matters, but for their own sake they need to stay anonymous.
If its just a document, then the "source is the document". You don't need to quote an anonymous person (who likely has their own biases), you just quote the document itself.
These words that journalists use? They have meaning. "Anonymous source" is not how the story is described. It is described, rather precisely, as "internal documents".
In a journalistic context, a source is a person. That's why words like "my source" are used.
Ex: lets say New York Times reporter was let into Twitter HQ for some kind of interview. The reporter noticed that a computer was open, so they stuck a thumb-drive in and grabbed the document.
No human source, but the document is likely valid.
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Alternatively, Twitter could have posted some document to an internal Slack or Discord meeting, and New York Times reporter may have the know-how to enter into those private channels or grab something from Discord.
There's no reason to assume that they worked with a Twitter insider to grab this document. Not everything is a leak. Old school Journalism is basically spycraft, a reporter can sometimes just grab something to get a good scoop.
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Or maybe the slides were just laying around on a table, printed out. Etc. etc. So maybe its not a computer document at all, but a bunch of slides that they dug out of the dumpster.
You’re literally commenting on an article citing “an internal presentation obtained by The New York Times.”