We've had such a huge support burden from folks using our Ansible-based "bare metal" installation (which installs packages via apt alongside other server software) that this week we simply removed those instructions from our web site, leaving only the Docker instructions.
We're a team of 2 volunteers. We simply can't support every imaginable combination of server software. Docker helps us ship images that are exactly as we want, with everyone on the same page. It's just that simple!
@murtezayesil I think Snaps, Flatpak and AppImage are all well-suited for desktop applications being distributed for end-users to run on their machines. In my case, I'm distributing self-hosted server software with a number of server components (nginx, php, redis, mariadb, etc) and for that, Docker (and even Kubernetes) is well suited.
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