It's just a shorthand way of referring to how transformer-based LLMs work. It should go without saying that there are hundreds of layers of hierarchical representation, induction heads at work, etc, under the hood. However, with all that understood (and hopefully not needed to be explicitly stated every time anyone wants to talk about LLMs in a technical forum), at the end of the day they are just doing autocomplete - trying to mimic the training sources.
The only caveat to "just autocomplete" (which again hopefully does not need to be repeated every time we discuss them), is that they are very powerful pattern matchers, so all that transformer machinery under the hood is being used to determine what (deep, abstract) training data patterns the input pattern best matches for predictive purposes - exactly what pattern(s) it is that should be completed/predicted.
The only caveat to "just autocomplete" (which again hopefully does not need to be repeated every time we discuss them), is that they are very powerful pattern matchers, so all that transformer machinery under the hood is being used to determine what (deep, abstract) training data patterns the input pattern best matches for predictive purposes - exactly what pattern(s) it is that should be completed/predicted.