alt Hacker NewsOCI image repositories are pretty ubiquitous nowadays and are trivial to setup.
I am sure that a lot of people have them deployed and don't even realize it. If you are using Gitea, Gitlab, Github, or any of their major forks/variations of you probably already have a place to put your images.
So I really don't know what the advantage of 'single file distribution model' is here.
This is probably why people don't bother sharing tarballs of docker images with one another even though it is has been a option this entire time.
If you're sharing with lots of people registries are great.
If you're deploying to a server, I don't see a point in setting up a registry, regardless of how trivial it is. It seems even more trivial to just send the deployment package to the server.