An infant scrawling the alphabet in its own excrement would have that "signal"...
We arrived in the era of Effective Content: judge a book by its content, not its cover.
E=MC^2 expressed as AI slop article still is light-years ahead of any of, say, Deepak Chopra's work no matter how polished, well-thought or painstakingly handwritten it was.
If I had the algorithm for AGI and I would let Fable write some slop about it you'll still sell your own mother to read it. It's not the form, it's the content.
I used to use other signals to help judge: literacy, reputation of the writer or publisher, the media they used to communicate. Now even governments are distributing notice of official policy through poorly written tweets, yet the Internet is flooded with whole websites of AI slop that looks on the surface to be professionally made. We lost the signals that used to help us filter out the signal from the noise.
The alternative is not to read all content carefully because we don't have anywhere near the bandwidth to do so. This article is about other ways we can provide those signals. Even if the content is crap, the fact that someone has to sacrifice to produce it limits the amount they can produce, requiring them to prioritize what they produce, and signaling that this was important enough to them that it was worth the sacrifice.
When someone takes the laborious effort to provide a short paragraph on an insanely complex topic, precisely written without excessive hedging or jargon, and conveying a shortcut or mental model, I know they worked hard on it. That is still a valuable signal. No amount of fancy medium can top a well-framed idea concisely stated.