The thing is, that returning to your notes is the
least important part of taking notes. What writing notes longhand does is do a better job of encoding what you're taking notes about into your long-term memory.
Anecdata: As part of an ongoing project,¹ I spent about two years teaching myself Biblical Greek. As part of this project, I ended up filling a couple notebooks with handwritten notes—writing out tables of conjugations for every verb that was taught, handwriting translations to and from Greek, etc. What I found was that even though I never actually went back to the previous notes, I had good recall of the information that I practiced in this fashion. I think (but what do I know?) that part of it was the spatial component to the note-taking. I can't find stuff in code that I've written without searching,² but I could go back to my handwritten notes from learning Greek (2017–2019) and find, say, what I had written about the aorist passive without much difficulty.³
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1. https://www.dahosek.com/category/dewey-decimal-project/
2. You might think, “big deal—then search” but what if the search is not by some thing easily turned into text but rather some concept which I don't remember exactly what I typed to do it, or the searchable thing ends up being some bit of text that recurs so frequently that the search is effectively useless. I have a much easier time finding things I've read on paper from my personal library of around 1200 printed books than I do finding something I've read online even with the fast searching capabilities of the internet (although I will admit that it's a lot easier to find disposable writing again online than in print).
3. That spatial context helps in other ways too—I can find things from grad school notes (2002–6) pretty easily as well and there was one time in 1999 that I pulled up a quote from a book that I'd read in 1992 (which had no index) in just a couple minutes thanks to my memory of roughly where in the book and where on a page spread the passage appeared.⁴
4. Yes, I know that, especially with that last anecdote that I'm getting into stuff that's likely well outside the norm, but the basic point that spatial context helps with memory is something that's well-studied and documented. We don't get that with typing on a screen.