I can't find who's the source on this. The best I can find is "people familiar with the investigation", but both the FBI and Cellebrite refused to comment on the story. This article quotes Bloomberg, which seems to be a copy of the Washington Post's article without all of the fluff.
I'm not surprised, there was a recent report that showed that Cellebrite can unlock any phone except for recent iOS and GrapheneOS. I'm just confused who "the people" that are being quoted everywhere are supposed to be.
It's an anonymous source. Someone who knows something and isn't supposed to say it, so figure someone at the FBI or Cellebrite most likely. Anonymous sourcing is a fraught practice, but often a necessary one if a journalist doesn't want to be restricted by what an organization will officially allow. You have to evaluate the publication, the journalist, and whatever details are available to decide if you want to trust them.
Its a claim that won't be confirmed and even if verified might be a lie to hide some better tech or just inane CYA. As an example, there is still nonpublic Kennedy material. Why would this event be any different?
I'm not surprised, there was a recent report that showed that Cellebrite can unlock any phone except for recent iOS and GrapheneOS. I'm just confused who "the people" that are being quoted everywhere are supposed to be.