Brevity is the big disaster of human-generated text since the rise of the phone as default device and the appearance of Twitter. To discuss matters with sufficient depth and nuance, one often has to write a few solid paragraphs.
If people are now wincing at longform text because they automatically assume it was LLM-generated, then that bodes ill.
To add to this, there seems to be an inability to process metaphor and simile in the younger generations. Likely as a result of the same deficit. They've become very literal, and often mistake anything that's well written for AI slop.
"poisoning the well"