I am pretty tame on FB, and in real life too--but this particular issue bothers me to no end, and no one else really seems to care nearly as much as I do!
It makes absolutely no sense, and even if it did make sense at some point--150+ years ago, why would we continue to use it? Moving from the west (CA) to Colorado (which is sorta centralish but at least reasonably could be considered mid-westish) did nothing to clear up the confusion.
Back on topic: I too have that one FB friend who goes off on cringy rants. He's a good guy. Years ago I got him into IDPA. He retired and moved to NH to be part of some conservative utopia which never really went anywhere. Thankfully, it's only occasional, but when he gets triggered I just wonder what my other friends think.