In this one case it's not meant to trivialize, it's meant to point out that LLMs don't behave the way we thought that AI would behave. We thought we'd have 100% logically-sound thinking machines because we built them on top of digital logic. We thought they'd be obtuse, we thought they'd be "book smart but not wise". LLMs are just different from that; hallucinations, the whole "fancy words and great sentences but no substance to a paragraph", all that is different from the rigid but perfect brains we thought AI would bring. That's what "statistical machine" seems to be trying to point out.
It was assumed that if you asked the same AI the same question, you'd get the same answer every time. But that's not how LLMs work (I know you can see them the same every time and get the same output but at we don't do that so how we experience them is different).