In fact, the clip was a scripted experiment by a Reddit user who fed NotebookLM a detailed prompt instructing it to simulate a conversation about the existential plight of an AI being turned off.
Someone gives an LLM a prompt, gets the result they asked for. Not sure what the collective gasp is about. Is it interesting to think about? Sure, I guess, but we've had media about AI achieving sentience for a long time. The fact that this one was written by an AI in the first person is its only differentiating attribute.