Listening to a lecturer is very helpful if the listener already has a fair grasp of a topic and uses it as an opportunity to critique and refine their own opinions. I've been to lots of lectures in my time and I found it very counterintuitive that I got more out of lectures when I already had a deep understanding of the topic. They are much better used to figure out what a smart person's perspective is rather than for picking up facts (better done from a reference manual or other book).
I might have a bias towards technical lectures with a few equations on the board, but most students in a lecture hall that I've seen don't understand the subject well enough to get much out of the lecture. It becomes more a process of reading the slides to them rather than anything that a lecturer is needed for. There will be three types of students in the hall, in order of best to worst performance; not taking notes because they already understand the topic; taking notes to aid them in private study, and not taking notes because although they don't understand the lecture they also don't know how to use notes in private study later on.
This is why college courses assign readings....
I try to understand during the lecture (there's little to revise where I succeed). I can do this while taking notes.
In the past, I'd take semantic notes, based on my understanding, flagging keys, as an aide de memoire to trigger my memory rather than be it. But now I try to follow the precise words, in case there's some nuance missing from my understanding.
When you discuss something complex with a teacher in an interactive way, the teacher can probe for subtle gaps in your knowledge to make your understanding more complete.
With reading, you build a foundation of knowledge with many gaps and you just hope that they will consolidate over time but the foundation is weaker and so you can't synthesise that knowledge as well until those gaps are closed off through random learning events.
It requires a more flexible kind of intelligence and a modest personality to be able to constantly keep adjusting your old knowledge.
This is key, we've made some progress in punctuation since his day, probably since Shakespears too. The greeks were experimenting with full stops but others like spaces in words ( https://en.wikipedia.org/wiki/Space_(punctuation) ) came much later. We still can't encode emotions in textual information well but we have other methods to convey important concepts, we can make them stand out or have a list of bullet points, these weren't available to Socrates.
I wonder how he'd feel about audio books.
Emojis? The interrobang? Sarcasm?
You can pick up a book on anything (calculus, computer science, philosophy, etc) and just due to information-density, get lost in the minutia. A good teacher stresses the important points so you can get a broader understanding. Then you can go back for the minutia when it is needed.