This is an official docker image - official here is an adjective for docker. Think of it as a debian package.
In debian, I wouldn’t need your agreement to make a debian package (except if you specifically disagree).
In docker, it is a docker policy, I need an agreement from you, it is better.
This still doesn’t mean you have to support it. We could still state that the official way of installing it is with the laucher and this is not official discourse thing, just a community effort.
Ok, just realized it was the wrong link in the original issue, I pointed to this issue with a bit more background. (will updated the post)
I’m running this docker-compose since 2 years in production.
I host around 5 forums with that, the last one being forum.chatons.org a collective with 58 free software hosters in France.
I already created 4 official docker images (rocket.chat, Nextcloud, piwik..). And also did the official helm chart for rocket.chat.
As a day job, I work as a consultant to help companies to migrate to kubernetes.
During my docker trainings, I actually make people dockerize discourse 
I find it nice as it is a real example!
I developed a docker-compose PaaS called libre.sh and we are rebooting the project with kubernetes. I just think that I’ll migrate first the discourses, that’s why I’m here again to discuss about this topic.
What makes me want so hard this official image is the talk for the freedom box. I want to push my changes upstream to collaborate. Of course, I can maintain my little docker image on my side, but many people are doing the same, and it is so much valuable engineering time lost.. it makes me sad.
I hope I managed to convince you, i still have some arguments in my pocket!