How is OCI terrible for reproducibility and security? They are certainly more reproducible than what we had before. I haven't heard "Works on my machine for a long time". If you're talking about reproducible builds, there aren't any hard issues either that are directly caused by OCI images - except setting the clock correctly.
> Boot images should be Dm-verity protected EROFS images
Maybe I'm misunderstanding you - I gather that you think the boot images are distributed as OCI images? That's not the case, bootc is more about building the image, updating it and the overall structure. Booting an image built with bootc does not involve any container infrastructure (unless you start services that depend on containers, I guess - but that's deep in userspace). There's technically nothing preventing this from using verified read-only images.