Two points not have been mentioned:

1. (Re)tagging leads to a change in the updated time, but reassigning a note to some other notebook does not. This is very important for the sorting habit by updated and created time. That’s why I am a little concerned for using tags.

2. Selecting parent tags does not show all the notes with child tags, but selecting parent notebooks does. However, from the favorites bar, one can choose any tags, but not parent notebooks. Interesting, hah?