As a professional editor, I would say that the expression you decry is legitimate, if not overused.
But as a “Freeper,” I would agree that the expression is frequently a signal that some pseudo-outrage is about to follow.
In short, when used to explain the speaker’s qualifications/credentials or perhaps special circumstances which led to his statement, the phrase is helpful. However, when meant to suggest that the speaker’s opinion is sacrosanct or to warn in advance that dissent will not be tolerated, it smacks of brow-beating.
I just realized I’VE used this very expression when writing nasty letters to my senators.
I start out “As a soldier’s mother...”
...and proceed with my brow-beating and list of complaints against them (my senators) and their wrong-headedness...