I think Ralph has a point.
Perhaps an 'in mil' / 'ex mil' split would work. Who knows?
My take on PPRuNe Mil is that it is a continuation of Mess Happy Hour / Squadron Beer Calls / Section Piss Ups etc
Banter. serious, lamp-swinging, informative, historic, all types of chatter is here.
Besides, where would us sad old ex tossers go for our fix?