If attending university was merely a means of satisfying your intellectual curiosity, we wouldn't be concerned about legacy admissions. The problem is that a university education is seen as the only viable path to a good life and a good career, and elite universities being one of the few paths to membership in Western society's elite class. So in effect, a lot of young people are pushed into getting a university education so that they can have a good life.
> No, you cannot replicate being taught by one of the brightest minds in a field by reading their published work.
Personal mentorship by one of the brightest minds in a field is indeed difficult to replicate with YouTube videos and online courses.
Undergraduate-level lectures taught by bored TA's? Video lectures are almost certainly a superior alternative -- especially if the student actually has that intellectual curiosity and initiative.