This was intended as a DM, but I couldn’t send it. I think it’s fine as a public post in the Feedback category, given it is feedback, and even if addressed to you in this context it is not actually personal feedback as much as food for thought for the mods team.
A two-cents piece of feedback on moderation: I think referencing the Code of Conduct explicitly could be good in cases like this one: Why hasn't "Qubes way" become standard? - #13 by Sven
What makes me think that
On one hand, I get your point when replying to zithro. (And I do think their reply was indeed not appropriate for the forum.)
On the other hand the behavior that unman called out is explicitly mentioned in the Code of Conduct (quote below), that all users agree to follow by participating in the forum (whether they read it or not); and I believe that calling it out was indeed appropriate.
I’m saying this because without mention of the CoC, unman’s post might fall under the criteria you posted for off-topic or undesired thoughts in the context of the forum. I would find such a side-effect unfortunate, and to my summary above: I think a reference to the CoC is a good discriminant in cases like this one that removes any kind of ambiguity.
With all thay said, I don’t think you did anything incorrect! Those are two-cents worth of thoughts in the spirit of making moderation more effective, and very much food for thought as far as I’m concerned, no action needed!