How does being a member of a women only social app give these women and advantage over anyone else? How does it adversely impact those who are not allowed to join? I can tell you that if they allowed these Trans "people" to join they would be a disruptive force on the app, possibly causing the apps demise.
When places like Augusta National were forced to allow women members it was because this organization was determined to be a place where business and employment opportunity are routinely conducted. Thus, disadvantaging those who are not allowed to join. There are many men only and women only organizations that are legally allowed to exist.