Yes. And most importantly, the Incus API and CLI client (which uses the API) presents a consistent management language for system containers (the default ones with a init/systemd-controlled userspace), OCI containers (unpacked, not layered), and VMs. Well, as consistent as makes sense for each. There are a number of options/properties that are specific to each, but it feels very consistent.
The Incus server inside IncusOS is the same software. The difference is as little userspace as possible alongside it (not even busybox).
The Incus server inside IncusOS is the same software. The difference is as little userspace as possible alongside it (not even busybox).