A modern LLMs corpora is every piece of human writing ever produced.
Apart from the fact that that is utterly, demonstrably false, and the fact that corpora is plural, still the fact remains that we don't speak in those text about things that don't need to be spoken about. Hence the LLM will miss that underlying knowledge.
Not really, but even if it would be true, I don't think humans ever explained to each other why do you need to drive to car wash even if it's 50 meters away. It's pretty obvious and intuitive.