The fact that there are 56 heavily-populated PUA forums deserves some attention. The fact that forums are still used deserves attention. There should be a better platform to address questions, share stories, and share links.
For a community driven mainly by external content, something like HN/Reddit makes sense - the links are the focus.
For a community driven mainly by the visitors' experiences and opinions, a forum is still a remarkably versatile and useful tool.
StackOverflow... StackOverflow is built around factual answers to exact questions, rather than open-ended discussion.
Nevertheless, you don't see the PUA community frequenting reddit.com/seduction. Don't know the % of them who actually know what Reddit is. I don't know of any one true "base," for lack of a better word, to find good PUA content (ex: TechMeme for tech news).