Can anyone explain why Docker image handling is so terrible? For one, building an image creates lots of unnecessary overlays (resulting in the absurd need for "

Can anyone explain why Docker image handling is so terrible? For one, building an image creates lots of unnecessary overlays (resulting in the absurd need for "garbage collection"), rather than just compacting everything into one file? But also the whole registry thing. Why can't I just point Docker at an S3 bucket? Sure, you can run a private registry, but that involves (last I checked) running a daemon, Redis, and using "docker login" to get credentials set up... instead of, you know, a file path (like an NFS volume), an HTTP URL, or an S3 bucket. The registry seems like a nice thing for publishing public images, but it has nothing to do with private images.