I agree with this approach. That way a note would be specifically made for searching a specific topic. I would use this in the example of Leetcode Problems.
Leetcode Example
I can have a section for difficulty (easy, medium, hard), algorithmic paradigm, data structure, status (solved, unsolved), etc. Then by ctrl-clicking it would be quick to form a search and find my desired problem.
This would also solve my issue with nested tags. By having each of these leetcode tags nested under the tag leetcode, I have a lot of clutter on the screen given that a problem could have the tags: leetcode/binary-search leetcode/array leetcode/hash-table leetcode/solved leetcode/divide-and-conquer leetcode/sorting… Or even worse if I wanted to further categorise the tags (for example according to the categories listed in the above example).
Further Examples
Some further examples that also come to mind are: recipes, movies, places…