There's a very neat project (can't remember the name, and some details below may be wrong,) that mounts a FUSE filesystem that uses only tags.
Paths have identical syntax to hierarchical ones, only each segment of a path is a tag.
so `/document/taxes/2020` would return a collection of files, but you could also write `/taxes/2020/document` and it would mean the same thing.
The advantage is you can use standard unix tools like ls, mv, cp, etc. as well as R/W using standard programs (like how you'd export an image.)
I'm sure there's edge cases to it, but I always found the idea very neat. Anyone remember what I'm talking about?