This is actually a pretty natural fit, imo. Docker containers are basically processes with fat runtimes, and container orchestration layers are essentially glorified process supervisors.
At the same time, most Linux systems already come with a pretty fancy process supervisor. Personally, I think writing systemd units from scratch is already pretty easy. But it makes sense that Linux software which often integrates with (essentially) process supervisors would want painless integration with systemd!
Also, in some ways I think this is simpler. Anyone who has used a reasonably modern Linux likely has some systemd experience. For local testing and 'orchestration', why rely on some additional one-off layer like docker-compose when the operating system's built-in process supervisor has all of the facilities you need?
Not really. Being simpler would be managing containers directly with systemd, as with systemd-nspawn. Why do I need to use a container manager in systemd for something systemd can already do directly? This integration with Podman is Red Hat's way of promoting the tool to stay relevant, but it's not actually simpler.
> container orchestration layers are essentially glorified process supervisors.
There is a little more to container orchestration runtimes. Would say at this time they are akin to a badly designed, distributed linker (I'm saying this as someone who did not fully buy into this stuff, but I see that it solves some problems)
At the same time, most Linux systems already come with a pretty fancy process supervisor. Personally, I think writing systemd units from scratch is already pretty easy. But it makes sense that Linux software which often integrates with (essentially) process supervisors would want painless integration with systemd!
Also, in some ways I think this is simpler. Anyone who has used a reasonably modern Linux likely has some systemd experience. For local testing and 'orchestration', why rely on some additional one-off layer like docker-compose when the operating system's built-in process supervisor has all of the facilities you need?