First of all, neural nets do nit return averages per se. They construct space between the points and extrapolate outside of the points. So even if a point was not in their training data, they will be ok, in many situations, to acknowledge it.
Or in other words - LLMs don’t average. They construct world models. A novel thing that fits their world model will be accepted no prob. A thing that doesn’t may still be accepted but with challenges.
The same is true though for humans, including scientists. There is a saying that science moves one grave at a time - because often prev gen of scientists needs to die off for a new idea to take root.
Or in yet other words - even if llms produced averages, an average of a discontinuous set can lie outside of that set. And the set of all human ideas is very much discontinuous.