Maybe there's an analogy to our long and short term memory - immediate stimuli is processed in the context deep patterns that have accreted over a lifetime. The effect of new information can absolutely challenge a lot of those patterns but to have that information reshape how we basically think takes a lot longer - more processing, more practice, etc.

In the case of the LLM that longer-term learning / fundamental structure is a proxy for the static weights produced by a finite training process, and that the ability to use tools and store new insights and facts is analogous to shorter-term memory and "shallow" learning.

Perhaps periodic fine-tuning has an analogy in sleep or even our time spent in contemplation or practice (..or even repetition) to truly "master" a new idea and incorporate it into our broader cognitive processing. We do an amazing job of doing this kind of thing on a continuous basis while the machines (at least at this point) perform this process in discrete steps.

If our own learning process is a curve then the LLM's is a step function trying to model it. Digital vs analog.