LW has a problem. Openly or covertly, many posts here promote the idea that a rational person ought to be able to self-improve on their own. Some of it comes from Eliezer's refusal to attend college (and Luke dropping out of his bachelors, etc). Some of it comes from our concept of rationality, that all agents can be approximated as perfect utility maximizers with a bunch of nonessential bugs. Some of it is due to our psychological makeup and introversion. Some of it comes from trying to tackle hard problems that aren't well understood anywhere else. And some of it is just the plain old meme of heroism and forging your own way.
Title is misleading, I thought you were going to talk about self-improvement in general for which this was an interesting statement but it's about academic learning so why not "against lone-wolf learning"? What you said is both, (1) already consensus pretty much everywhere, everyone thinks taking classes is best, it's improbable that even someone from LW isn't aware of this viewpoint (2) clearly wrong, but not something I feel discussing and I'm only replying to complain that I was click-baited into reading this.
I don't see how this is limited to academic learning.