I'm not the OP, but I think everyone might have a different definition of what "audible inner monologue" mean.

For example, I don't talk to myself in "monologue". But I can close my eyes or stare at the screen and visualize the solutions. The words that I usually tell myself during that are "what?", "why?", "strange!", "really",... not a monologue or sentences.

The author says they could narrate their own thought process out loud.

I couldn’t do that. I have no insight into my thought processes whatsoever. There are no semantic (or any other) processes to witness. It’s complete crickets at all times…

My wife is the opposite - constant chatter in her head. And she can trace every thought exactly. (No idea how people like her can focus or even function!)

I am such a person and I've always done 'chain of thought' in a notepad in order to think through complex things, well before LLMs were a thing. There are certainly tasks I can 'one-shot' but I've learned from experience that for some problems that just results in me focusing on irrelevant things.