"Recycling things people have said before" is basically search, and that is hugely valuable and quite enough for me. If it's genuinely generative, that's a cosmic leap beyond search.
My guess is that it's not genuinely generative, but rather that the long tail of "everything that everyone has said before" is so vast as that it feels like magic when it's retrieved.
But LLMs have shocked me enough on the search front that I'm no longer smugly confident about this.
I'm not much of an LLM user, but the few times that I did turn to it for programming advice was in rare and obscure situations that weren't really discussed anywhere on the internet (usually because they contained multiple issues in one). The LLM tended to produce something I'd call a reasonable answer, especially on topics that weren't completely obscure.
But we don't even need to go that deep to answer the question. For example, if an LLM was pure search, you couldn't make one generate text in some specific style or with specific constraints, unless that exact answer already existed somewhere on the internet. They can mash up ideas or topics, and still output good or reasonable data.
The billion dollar question isn't whether it's generative - it's whether the generative capabilities are "enough". Machine learning is about finding patterns, and a complex enough pattern finder will be very good at approximating answers accurately. LLMs don't actually have an accurate "model of the world" learned - but they have something that's just close enough on certain topics to make people use it as if it does.