I intend to exercise the ability of moderators to issue hats to the community user. The festivities will commence once the proper code is issued to the web engines.
Community, please show some holiday spirit!
And we're up and running...
Questions with no or no upvoted answers (as the one referenced in the question) will get reinfected into the front page a few times automatically to get more attention. As no user is involved the user is shown as "community".
Like many users, community has a profile page that explains what they like to do on the site. In this case, community is a robot ...
In general comments are considered to be temporary information which can (and sometimes will) get deleted once the objective/purposed of it is reached.
The purpose of comments as such is documented in the Help Center:
You should submit a comment if you want to:
Request clarification from the author;
Leave constructive criticism that guides the author in ...
That looks like something from before the redesign of /review. (Or an artifact for when a user's account is deleted). Either way, I've not seen any recent reviews by the community user.
Unless you can point to something more recent, I'm inclined to close this as status-completed at this point. It's fascinating, but likely to be a relic from the past.