I'm going to push back on your pushback and say you're not disagreeing with me.
I was referring to a hypothetical future where everything has gone through AI to some degree, and for the purpose of the argument it has been modified enough to embed a watermark. Thus, the "detector" just always returns "true" in practice, and therefore nobody cares about what it says anymore.
I think what you call "aura" in your essay is already very much a thing. We use the adjective "artisanal", for example. Artisanal, bespoke, heirloom. hand-crafted, small batch, ... we have many ways of trying to convey "aura". (Heck, even things like "minority-owned" or "woman-owned" are attempts to imbue an aura.)
But more to the point of text, I'm also fascinated by the evolution of taste in this area. People's ability to detect AI slop improves, triggers revulsion to things they were previously fine with, and then sometimes they'll go back to being neutral once they start using AI more heavily themselves. Some AI writing is noticeably better quality than the human written version, yet it still smells of slop, and I at least am sometimes torn about which I prefer. Then there's the trend of AI writing getting better, substantially better, and sometimes at the same time worse in certain ways. Not to mention students, many of whom are now much more accustomed to AI writing than human writing -- it's their mental model of what an essay looks like, especially when all of their own essays uncoincidentally read like AI writing. And then there's all the nuance of the sometimes subtle differences between a wholly AI-generated piece of writing vs a heavily human-directed piece of AI writing vs an AI-edited piece of human writing vs a translated piece of human writing. It's fascinating and scary.
I too am curious about the final question in your essay: "will such categorization lead to the development of a potential human premium?"