A note on folders: I think grouping is a good thing alongside linking notes. I like to combine both methods, but instead of sorting notes into folders, I tag them. For personal knowledge bases it's probably fine to "silo" everything, but I found it really useful to add tags to notes when collaborating on the same knowledge base with multiple contributors. That way I don't need to rely on someone elses judgement and can group them from my perspective without colliding with the author. So instead of having folder -> articles, I have article -> tags and an can query by tags.
Emvi [1] has a tag overview page to allow just that, in case you're interested. I'm using it alongside 7 other people, where 3-4 are actively contributing to it (writing).
No, Emvi does not support private tags. But usually you won't need many tags to identify it for everyone. I was looking for the fixed IP addresses of our local network recently and couldn't find them by searching for "IP", because it was tagged as "network". Adding IP as a new tag is beneficial for everyone.
You can bookmark, watch, or create a (private) list for stuff you look up frequently.
Emvi [1] has a tag overview page to allow just that, in case you're interested. I'm using it alongside 7 other people, where 3-4 are actively contributing to it (writing).
[1] https://emvi.com/