Women have the right to their own spaces. But cis women do NOT have the right to exclude trans women. That kind of thing is pure transphobia. It's like saying that trans women aren't women. Yet historically, so many "womyn only" lesbian spaces have allowed trans men in?? How the hell does that make any sense? Trans men aren't women; they're men! Trans women are women!
So, because women (cis and trans) experience sexism and have different experiences from men or non-binary people, they are absolutely entitled to their own safe spaces. If someone is defining "ladies" or "women" or "womyn" by genitailia or anything other than personal identity and experiences, it's problematic as heck.