"A critique is not ad-hominem if the target is a character trait relevant to the speaker's point."
As I interpret your sentence, that is not what the article you are quoting says, and it is also not correct. This is irrelevant here, however, because the character trait being discussed is not related to the speaker's point; it is merely an argumentum ad hominem.
As I interpret your sentence, that is not what the article you are quoting says, and it is also not correct. This is irrelevant here, however, because the character trait being discussed is not related to the speaker's point; it is merely an argumentum ad hominem.