[cyphar]

OCI is the "standard", it's just that nobody actually uses it. Everyone is still emulating the Docker format, and Docker doesn't even support OCI images (the pull request adding the most basic form of support is 2 years old[1]).

For the record, I work on the OCI specs (and maintain runc and image-spec) and would really love it if people actually used the OCI formats and we could freely innovate in an open spec. But that's not really the world we live in.

(I'm aware containerd supports OCI images and most folks now support the runtime-spec. But how many people use containerd directly? Not to mention that since the OCI distribution-spec is creeping along so slowly everyone still converts back to Docker to actually publish the damn things.)

[1]: https://github.com/moby/moby/pull/33355

[praseodym]

Recent containerd versions have CRI support built in, so Kubernetes (Kubelet) can use it directly.

[cyphar]

Images are still pulled from Docker registries, and thus there is still conversion to OCI rather than OCI being the primary format. cri-o has been doing the same thing for the past few years.