But how to solve the problem of boys who identify as girls (and vice versa) while protecting the safety and comfort of those who have always been girls (or boys if the case were vice versa)? That's the dilemma for Girl Guides as for other groups.
It's similar, in a way, to feminist concerns about trans women in women's sports. Men identifying as women, understandably, want to participate in women's sports, but Ive heard that their masculine abilities make it difficult for genetic women to succeed, apparently, and so appear to be setting genetic women back in sports achievements.
The most logical next step in all these cases would be, it seems, to create separate scout/guide groups/sports events for transgender girls/women and transgender boys/men. But then, that would probably be criticized as bigoted and segregationist, even if only intended to ensure everybody's comfort. Very tricky situations. I'm not sure what the eventual solution will be.