Yeah, that's how editing works. Both I and the author know this.
On top of that, however, an editor can have other causes in mind for flagging a sentence (either explicit or unconscious motivation), besides it "being crap". And if they do this frequently enough, one can discern a pattern.
To put it another way, a cigar is something people smoke. But sometimes (to reverse the know quote) a cigar is not just a cigar.
Similarly, an edit it's not always an edit - sometimes it's imposing an ideology behind the editing.
>It's not a convincing piece of evidence
Part of the essay is about how for some of those cases there's no evidence, but you can see it if you come from the right (constrasting to the editor) background. And where it's more obvious, there's still "plausible deniability". It's about about the emerging pattern of editing decisions.
And like many things in life, you either see it or not. It's not a court case, or a math proof, it's more like a joke. You can't prove it is funny to someone, you can just find it funny or not.
It's not a convincing piece of evidence to point out that an editor removed a nonsense statement as evidence that the editor has ideological motivations. It's not proof that they don't have ideological motivations. It's just an irrelevant edit of a bad phrase.
This feels like the classic Community scene in which Chang is trying to pitch "Bear Down for Midterms" as the school's slogan, and everyone says "What does that mean?" to which he tries to defend by asking if their issues with it are a race thing.
The author's thesis can be correct even if his evidence and persuasive reasoning are bad.