Handwriting definitely helps, but a lot of it in this system is done during reading (or just general life), which Ahrens calls "literature notes". Ahrens has a theory that handwriting forces paraphrasing, which he views as important to learning. Anyway, I handwrite all that, then there's a later stage of integrating the relevant info into the system.

For me, searchability and accessibility, plus backup (I write a ton on paper already and I'm a bit worried about losing notebooks) makes it worth the digital step.

Also, I suspect from initial usage that the Zettelkasten is what Krakauer calls a "complementary cognitive artifact": https://philosophicaldisquisitions.blogspot.com/2016/09/comp...

I.e., it makes you better at what you're trying to do even in the absence of the tool. To me, the main benefit of the system is that it encourages relational thinking.