I suppose an occasional separate sing-in based on age might make some kind of sense sometimes - definitely so far as children are concerned. Maybe some other age groups.
I don't know if that helps work out something about why some kinds of separate groups seem fine, and some don't. I think it's to do with helping people who get drowned out otherwise to find a voice. Not that there's anything subdued or quiet about most of the women I know. But I can imagine that the ones that are subdued and quiet might get more support and help in a woman's group than in a mixed group. And that probably wouldn't be true of most men only groups.
And I have come across some very confident and powerful women singers who have said that until they went to a women's only workshop they had never felt able to sing in public.
Not that all this is too relevant to a Hear Me. I'd imagine. But this thread seems to be turning towards wider issues, as they do.