In this case, it's probably justified to have gripes with the editors.
They got an opinion piece with an extraordinary claim about something the writer saw in a slide presented at a trial. She wrote the entire article about it creating theories and then how it needs to be stopped. Not to mention, she had previously worked with a competitive search engine. The central piece of fact checking was seeing that slide, that would have been the second question after "Are you sure you saw something like that?". The entire article hinges on that one slide she saw and what she understood from it.
This is not a case of missing a boundary condition. This is missing the central premise. At any level, it would be inexcusable.
PS: In a sense, as the artifacts are becoming public, i think more such confusions would surface in the coming weeks where merely misunderstanding what is on the slide would lead to a lot of rumors. Probably best we have an initial case and some intuition that this can happen.