The lecturers and professors you will find at university are not experts in pedagogy, and the vast majority will never have claimed they were. They are experts and leading active researchers in their chosen field. They have devoted their professional life to studying and extending the state of the art of knowledge in their chosen field.
If you want to study a subject at university level, it's likely that some of the material that you would learn at university is not yet in published books, because the only people who currently know the material are the researchers at your university who just discovered it, and are trying hard to find the time to write a book on it, around furthering their research, writing papers for journals (which they need to do, and which books do not count towards) and giving however many classes of lectures a week that they've been told to get on with, without a vast amount of training.
In grade school, the material you will learn are basics of subjects that have been understood for a while, and written and refined in books some time ago. The material can be understood by people competent (but not necessarily expert) in the field, and can therefore be passed on, or spoon-fed, by people who are expert professional teachers. This is required in grade school, because students in grade school are not yet adults, and generally don't yet have enough self-discipline and self-awareness to put in the work now for later benefit without being shepherded the whole way.
When you get to university, it is presumed that you are mature enough to have the self-discipline and self-awareness to figure out partly for yourself how to learn from the people who are the most advanced in the world in your chosen field, rather than the best teachers.
That presumption seems to have worked out pretty well for modern universities for the last 500 years.
Maybe university is not actually the place you want to be.