Part of the problem with these collections of notes, whether you call them Zettelkasten, Second Brain, PKM or whatever, is the expectation that something unique, amazing, or earth-shattering emerge from the process of using it. The expectation is strongest in the Zettelkasten community where they trot out the story of some academic sociologist of old who invented the system and cranked out tons of publications. Never mind that those publications have practically zero impact on the field currently. There is also the apparent expectation that you follow a specific and arcane method, with specific types of notes that evolve in a certain prescribed way. I’m a reasonably smart person and the ZK ontology perpetually escapes me. Maybe because it’s needlessly reductive. Yes maybe Luhmann used the system to generate a lot of publications. But the academics I know have never even heard of this. My spouse has a few hundred published papers and her process is nothing like this.
Anyway, I don’t see the point in destroying one’s notes. It seems performatively symbolic; and if that helps you get past a block of some sort, more power to you. My own notes are half-organized, half-chaotic. Vestiges of a dozen different systems live on in it. It shows that I suffer from collector’s fallacy. I don’t care.