Focus on the topics much or not
I have just discovered the Zettelkasten method a week ago or so, reading on it, going to try it and also just curious how people use it. In particular it is interesting to see stories of people who tried Zettelkasten much yet.. it didn't work for them - https://reallifemag.com/rank-and-file/
As much as I can read this post without being a Zettelkasten practitioner it seems like just having a relatively random set of thoughts and ideas connection (even good ones!) is not exactly enough for helping with producing something useful in the end. If Zettelkasten is to work similar to your second brain, is it somewhat similar to having yourself learned really well many topics in the area yet none of them deeply enough for producing some sort of a "big significant new idea(s)"?
So I am curious of whether this sort of issues are common with [new] Zettelkasten practitioners? Is it happening often that you end up with looking at a wide topic exploration when you need a deep one for e.g. developing your and world knowledge in some area?
Do you somehow consciously keep your zettels more focused on some certain topic(s) and avoid something that is likely to be not very related (for example, keeping off zettels learning on how your kids develop over time or just sudden revelations on the random topics that you discovered in a random blog post found on the web)?