So, first, most would say the purpose of a zettelkasten is to write. The book goes into this, that your notes eventually just get incorporated into manuscripts, and that your notes should be written as well as if you were writing a manuscript itself.
However, what really clicked with me about the book was the hypothesis that true human thinking can only be done externally, through writing, due to the limitations of our brain as a platform. The book lists out things like recency bias and short term memory limitations that get in the way of proper, structural thinking that results in actual insights. Whereas maintaining a zettelkasten, or a simulacrum of one at least, externalizes your thought process and allows you to achieve genuinely your maximum potential for thought.
The arguments went beyond the normal ones about the recorded benefits of note-taking for learning, memory, and creativity, and got into the aspects unique to a zettelkasten that make it an enabler for thinking. However the book also pitches this as a productivity boost for authors and researchers, and doesn't really seem to care about people who are just learning for the sake of learning (but it does make a solid case that building a zettelkasten makes learning more fun).
Personally I've been reading criticisms of the book as a way to learn how to maintain a zettelkasten that I agree with: it's not specific or clear enough, and it defines too many different kinds of notes (and not all at once; some note types are defined like 3/4 of the way through the book). For me it was just a very convincing argument to stop trying to make my brain do things it isn't good at - stop beating myself up trying to memorize super detailed facts, let my external system handle that. Stop worrying about forgetting bits and bobs of the various books I've read, let my external system slowly create a map of ideas of everything I'm reading. Stop over-optimizing all my note taking systems and just scratch shit into a paper pad, to be indexed as a good zettel later (or just thrown away if I decide it's not helpful).
So, though I do intend to use this system to fuel my blog, I think I'd still find value in it just in feeding the conversations I have as well. I'm deeply interested in non traditional politics, leadership, and activism, and with this system I've adopted I'm finding myself make connections I don't think I'd have made before; for example this very idea of externalization and scaffolding of human thought as a means to make up for our flaws, I'm finding similar threads in all sorts of things I read now.
If you're interested in zettelkasten, I would recommend a different resource for learning how to actually set one up (just, the internet plus chatgpt is probably fine, plus some FOSS software). I will say, if it's taking too long, whatever you're doing is too complicated. It should take a single click or button press to make a new note, and it should be very easy to scan through your notes and make links every once and a while, and making a link should be no more than a highlight, a button click or press, a search, and a confirmation. If you're anything like me, you may spend more time setting something like this up and agonizing over it than you will using it... that's why I moved from org-roam to trilium, so I could just stop hyper optimizing and start using the damn thing.