Tags are arguably superior to folders for organising files, unfortunately the major OS don't seem to agree. I'm using the same (expanded, adapted) folder structure for all my files since I got my first computer, and it's survived multiple OS migrations, being synced between multiple devices with different form factors, multiple changes in life circumstances (school, undergrad, postgrad, work),... I love tags and I've used them in some parts (eg in my old mp3 collection, for academic papers, for Anki flash cards) and I'd love to use a (simple and dumb, not rich enough to enable set theory paradoxes) tagging system to organise my files instead.

However, my experience has left me convinced that the only truly long-term solution for your personal data are flat files sitting on your hard drive inside a simple hierarchical folder structure. Anything else is likely going to rot at some point, after a system change, after some BigTech decides they want to use something else, after a start-up disappears, or it's going to keep you locked into some walled garden. Unless there's something I've missed, if so please let me know.