I guess I was a little to aggressive in my original comment. I meant to explain why minority only groups get less flack than majority only groups, not to suggest that men only groups shouldn’t exist.

Women only groups exist alongside the people who disapprove of them. I don’t see why men only groups can’t. As many have pointed out, however, men only groups DO exist. Someone linked to dull_mens_club as a Lemmy specific example, but more broadly, fraternities exist. Battered mens groups exist. I think some groups like nights of Columbus and the masons are or were men only. Men only schools and colleges exist, as do women only. Most veterans organizations are primarily men just by nature of who makes up the majority of most militaries.