> why wouldnt you at least stop using the obvious AI-sign, i.e. the long dashes

Em-dashes have a long literary history, which is where AI got them from, and they're genuinely useful in writing. We shouldn't let LLMs ruin that for us in literature. The fact that they've historically been less common in online writing is in part because of deficiencies in input systems, though they're easy enough to type with a compose key or similar, or a typesetting system that interprets `---` as `—`.