Also human can reason, LLMs currently can't do this in useful way and is very limited by their context in all the trials to make it do that. Not to mention their ability to make new things if they do not exist (and not complete made up stuff that are non-sense) is very limited.
1. The vast majority of people never come up with a truly new idea. those that do are considered exceptional and their names go down in history books.
2. Most 'new ideas' are rehashes of old ones.
3. If you set the temperature up on an LLM, it will absolutely come up with new ideas. Expecting an LLM to make a scientific discover a la einstein is ... a bit much, don't you think [1]? When it comes to 'everyday' creativity, such as short poems, songs, recipes, vacation itineraries, etc. ChatGPT is more capable than the vast majority of people. Literally, ask ChatGPT to write you a song about _____, and it will come up with something creative. Ask it for a recipe with ridiculous ingredients and see what it does. It'll make things you've never seen before, generate an image for you and even come up with a neologism if you ask it too. It's insanely creative.
[1] Although I have walked chatgpt through various theoretical physics scenarios and it will create new math for you.
Depends on your definition of "truly" new since any idea could be argued to be a mix of all past ideas. But I see truly new ideas all the time without going down in the history books because most new ideas are incrementally building on what came before or are extremely niche and only a very few turn out to be a massive turning point which has a broad impact which is also only usually evident in retrospect (e.g. blue LEDs was basically trial and error and almost an approach that was given up on, transistors were believed to be impactful but not a huge revolution for computing like they turned out to be, etc etc).
My personal feeling when I engage in these conversations is that we humans have a cognitive bias to ascribe a human remixing of an old idea to intelligence, but an AI-model remixing of an old idea as lookup.
Indeed, basically every revolutionary idea is a mix of past ideas if you look closely enough. AI is a great example. To the 'lay person' AI is novel! It's new. It can talk to you! It's amazing. But for people who've been in this field for a while, it's an incremental improvement over linear algebra, topology, functional spaces, etc.