My problem is that my personal AI detector running on wetware just goes ping and it's hard to articulate why. I agree with the person you're replying to on all points but also, when I think something is AI, it's very much just a little brain ping that I would have to laboriously try to work backwards from.

LLM text often just is missing the cadence of human-written text. It never slows down or speeds up; it keeps a relentless pace. Sure, a human can write like that, and I'm sure people do, but I find it enervating to read, whether it was a human or an AI that wrote it.