Yes, actually, there are. I've built https://clipper.dev. I'm somewhat focused on robotics/edge device use cases right now (handling large images in bandwidth constrained environments), but my storage costs are also 1/7th of DockerHub. It also enables device to device content sharing much easier than base Docker, will be much easier to do antivirus/vuln scans, some other side benefits.

If there's something you'd want out of a registry that you think the market would want, I'm all ears.