Nice points. The argument is though, we need to make installing and maintaining an instance easier and more accessible, so it requires less time and skill.
Right now, installing a production instance is a pain in the ass.
Meanwhile, Gitlab, which is a Ruby app too, has a way to deal with that: Omnibus package, which contains everything a Gitlab server needs to function, can be installed in three commands and upgraded via standard system package manager:https://about.gitlab.com/installation/#debian
I think Mastodon needs something like that.
Learn about the various GitLab installation packages such as Ubuntu, Debian, Docker, Google Cloud, and much more.about.gitlab.com