There is a lot being written about the stylistic tells of AI writing (em-dashes, etc.) but this paper looks at AI narrative tells
Fascinating differences between AI & human narrative, and asking AI to write in different styles doesn't do much to change it https://arxiv.org/abs/2604.03136
These all strike me as very true, based on my experiments with AI story-telling. They are also remarkably persistent. Story-telling has improved less quickly than most other AI abilities.