This entire article is the bad toupee fallacy.

Readers think they don't like LLM-authored text because they only recognize bad LLM-authored text as LLM-authored.

Blind trials have actually shown that readers generally prefer LLM authored books to human-authored ones on the same subject.

The "trials" you're referring to is probably this study on 1000-word short stories

https://www.cambridge.org/core/journals/judgment-and-decisio...