One thing to understand about moderation, any moderation: It depends a lot on context. We can not and do not want to create a fixed blacklist of terms and topics that will create an immediate call for moderator action.
In this particular case, I was the moderator "on call". I looked at the reported post, I looked at its context, and then used my knowledge of the people involved to determine if any intervention on my part was required. I didn't think that was the case; you, Nightmare, disagreed. As I said, you are free to do so, and maybe some other moderator will look at that stuff differently and come to a different conclusion.
As much as we may wish it, there is no definitive handbook for community moderation. All we can do is look at other communities and pick the parts that work and the parts that don't and see what we can do. I do not claim to be the ultimate authority on what constitutes good moderation; I am open to criticism and feedback on that topic.
That said, Nightmare, "You should no longer be Discord or forum if you consider this acceptable." is not what I would call useful as either criticism or feedback.