We run a service whose primary input is Dockerfiles; I'm not a Docker-hater. But doing the things we're talking about here in a systemd unit just isn't hard, and Docker, as you say, does a lot more than than systemd does.
Your comment would be better without the "rather embarrassing" swipe, for what it's worth.
There's less code for SystemD, but it's more complicated to actually use, and less useful. Docker is user friendly, and the features scale with workflow changes where systemd doesn't.
We run a service whose primary input is Dockerfiles; I'm not a Docker-hater. But doing the things we're talking about here in a systemd unit just isn't hard, and Docker, as you say, does a lot more than than systemd does.
Your comment would be better without the "rather embarrassing" swipe, for what it's worth.