I use them every single day. Because I maintain the folder hierarchy, I remember how to descend the folders to find what I need.
Years of experience has taught me that relying on loose tagging webs and searching mechanisms and fancy tools does not work for me, not for notes, not for emails, not for anything else. I organize things into nested hierarchies. This takes maintenance, but so does maintaining tag webs and using the tools to maintain and mine them.
For something that espouses some of these principles (though I do not use this system):
Years of experience has taught me that relying on loose tagging webs and searching mechanisms and fancy tools does not work for me, not for notes, not for emails, not for anything else. I organize things into nested hierarchies. This takes maintenance, but so does maintaining tag webs and using the tools to maintain and mine them.
For something that espouses some of these principles (though I do not use this system):
https://johnnydecimal.com