There should be a bootc backend for Discover to allow for updating bootc-based systems.
The rpm-ostree backend, while works for this, actually does not cover the case for a standalone bootc-managed system that does not rely on rpm-ostree.
I’m working on possibly adding this as an actual new backend in Discover, but I kind of need to figure out how to manage bootc updates since well, bootc has no proper API as of yet.
Also, it would conflict with rpm-ostree since they both provide the same update interface on rpm-ostree managed systems so you gotta deal with that somehow.