Standard teacher education says that each student has a learning style that is most effective for them. https://www.learning-styles-online.com/overview/

A person who learns well from books in a solitary setting is at a huge advantage compared to someone who needs a social-kinesthetic style.

It certainly is in comparison to someone raised illiterate, or in any number of unfortunate situations. But in comparison to the privilege of a university education? I'm a bit surprised by the suggestion. If self-taught knowledge is really the marker of privilege in 2020, I'd expect it to be far more attractive than going to university by now. On the contrary, it is not, because learning from books has a much lower bar. You can't use it to select for the well-connected.