There have been attempts to use s3fuse like layers, but:

> NOTE: I found it too expensive in S3 requests and CloudTrail data recordings to use S3 as the backend.

https://github.com/dubrowin/Immich-backed-by-S3

They used aws's own mountpoint for this. Perhaps s3fs with it's caching could do better? Ideally someone would make an object store fuse driver that caches the whole file tree & metadata, or perhaps storing on slatedb or some such. Being able to tune the local file cache would also be important: maybe maybe maybe s3fuse caching is good enough, but making sure thumbnails can cache seems super important. It would be interesting to see how immich uses the filesystem.