OK so, since when is a moderator’s judgement of whether an answer is right or wrong, a reason to delete it?

In this answer, https://electronics.stackexchange.com/a/342672/139766, the moderator deleted it because he decided that I had already mentioned some of the answer in a comment, despite the fact that the answer detailed far more than my original comment.

I understand, from the moderator’s comments, that he believes what I am saying is a non-issue, which is fine, and he may be correct, but since when does that give the moderator the right to judge answers, and delete them based on personal opinion?

I might understand it if it was marked down a few times... maybe... but not in this case.