This is something I really appreciated about some of my well-taught graduate classes (of course, "well-taught" is a big caveat). In undergrad there's often a sense that the professor is supposed to teach you the material. In advanced topics, though, I often found it most useful if the professor actually skipped most of the details, and served as more of a tour guide of the landscape of material for me. Once I know that some specific topic can be learned from a specific tutorial, book chapter, etc., then I can just go learn it on my own. But what's hard is figuring out how to make your way through this sequence entirely DIY, i.e. knowing what to read in what order, whether you're on the right track, where to look if you get stuck, and having someone to answer big-picture questions about how things fit together, why something that seems obvious to me isn't true, etc., etc. I've found some of the best courses helped with that.

A good textbook can also serve this role, but I've found good textbooks rarer than well-taught graduate classes. A lot of textbooks don't really seem to be designed for self-teaching the topic by reading it sequentially cover-to-cover. Maybe because they're often intended to be used in courses, they often have too much material, presented in a somewhat haphazard way, with an expectation that a course instructor will pick and choose parts and supplement it with lectures.