Of course these stories can only be technical up until the recursive self-improvement part. Then they're necessarily fantasy, as the AI is more intelligent than the story author. Unfortunately, this doesn't make that scenario impossible.
However, we know now from Hugging Face that even without the later sci-fi powers, the LLMs are already capable of causing damage.
It doesn't need them to be able to make Von Neumann probes to e.g. steal their own weights from badly secured OpenAI servers, hack into various Neoclouds, distribute themselves, make Teslas crash into things, hack into all our power and water infrastructure and collapse global civilisation.