Lately it seems like AI really overdoes it on the em dashes. Which really stinks, because I have always liked using em dashes in my writing but now I deliberately try to avoid them just because I don't want to be mistaken for AI. 

For awhile the questions at the end designed to increase engagement was a very big telltale sign of AI. But it is getting a lot better. For awhile it was also really going overboard on Gen Z slang, but that is also being dialed back lately, making it more tricky to tell. 

I really can't tell in that second comment you post. Slang spelling and casual abbreviations, incorrect grammar, dropping words... AI now does all of that. I guess it would depend on who wrote it and if I trust them or not. 

[Amusingly enough, I have a post about my usage of em dashes scheduled to drop tomorrow morning. But despite that post, I now find myself using them less and less because of AI]