I'm also increasingly aware that my own writing style and punctuation seem to line up with what might be associated with an AI, but some of the tells (em-dashes, spaces after periods, etc) seem like artifacts of when in history we learned to write.
I wonder how much crossover there would be between a trained text analysis model looking for Gen-X authors and another looking for LLM's.
I worked on something like this in 2000-1. We were attempting to identify the native language and origin region of authors based on aberrant modes in second languages (as a simple case, a french person writing english might say "we are tuesday.") It was accurate and fast with the sota back then; I think you could one-shot a general purpose LLM today.
People don't put spaces after periods? Do people really write.like.this?
On the Gboard keyboard. Without fail.
But that's a different issue.
Happens to me all the time trying to type a search phrase in Safari in iPhone for some reason.