Even if that's not how it started - and I believe it is, as well - that's what it's come to mean, among many (if not most) of the people who use it.

And @OP - as for 'unusually vitriolic' - really? In what way was that vitriolic, much less unusually so? It's not even as confrontational as a lot of similar comments I've seen - they seem to be going out of their way to be polite.