It is too complicated. We just get, save or write something, maybe with some categories, keywords, or tags.

After saving, maybe you need some organization later, but most time they are just there. Most time you search content by categories, keywords, or tags.

I think we need right tools for different requirements.

It depends on how you want to use your notes. If you're looking for a way to store information for later retrieval then what you described will probably work great. Zettelkasten is more about discovering connections between ideas that were not immediately obvious, and creating and discovering new ideas as you work with your notes.

Yep. I agree. This and other systems like it are for people who obsess over planning on doing work rather than actually doing any.