I do agree with your counter argument (and I think Ali Abdaal is kind of the poster child for that kind of exogenesis). Here's my dilemma: focus & flow vs. notes and pondering. If I'm reading a book, I can highlight something, but often the act of doing so -- especially trying to write it somewhere, or put it in an app -- takes me out of the flow of the experience. It's an interruption.

Not sure what the solution is -- periodic stopping points where you summarize what you've read? -- but it's a tough one.