Sure seems like it. Real humans don't write exclusively one sentence comments. It doesn't look like the post history of anyone here that I'm fairly sure is a real meat based mammal. It looks like someone gave an LLM an instruction to write exclusively short and snappy comments that are somewhat relevant to the original post.
In a vacuum a specific comment may be more or less fine, or just a tad over baked like the parent post giving it an uncanny valley feel but otherwise passable.
But even people who diligently try to stay on topic on a forum like HN will occasionally use a post as a segue or jumping off point to some other idea, tangentially related news, or random thought that pops into their head if it feels like it “fits”.
After scrolling through a few dozen replies in an account’s history that are all directly related to the post topic it no longer looks human in aggregate.
I’m sure the spammers will try to incorporate that idiosyncrasy into their prompts eventually but not sure it will help more than hurt.