I've run into something similar twice now in the last month. A candidate pauses or says 'let me think about that' on a relatively simple question as if to give an LLM time to respond. After the pause they give an overly long detailed answer - again like an LLM response.

One candidate was absolutely stumped and could not answer why and when they became interested in technology. They couldn't say anything about themselves personally. It was baffling.