Good to know Proxmox’s bad updates are more pervasive than the latest bad update.
I have been able to install Docker in the LXC containers and pull images in with the normal commands. I do that container-in-container to get effectively rootless docker containers for stuff that I couldn’t figure out how to run rootless. So you don’t even lose out on docker if you’re determined! And as you said incus goes on any OS, you can docker just fine on the base OS of your choice and use incus for specific things!