Suzanne S. Barnhill shared this with us in
microsoft.public.word.newusers:

My impression, though, was that most of the incivility here was
coming in by way of Usenet and almost certainly from the orphaned
(and deprecated) microsoft.public.word.general. By "here" I meant "in
this thread," but when I switched to "Show All Messages," I was
surprised to discover that "this thread" was not the one I thought it
was, but the comment still applies: note that none of the
participants are @discussions.com.

Indeed, you ARE correct!
In this case... for every rule there are exceptions.

My personal observation is that in most other cases the incivility
comes from "relatively new" users (more than 1 year but less than 5
years of internet usage), and there is a higher probability for a "new
user" to be on a forum, not on usenet.

--
Amedee Van Gasse