Oh c'mon. According to organizations that track these matters like the Williams Institute and Trevor Project, nearly everyone who "identifies as" non-binary is under 30. The largest proportion of people who "identify as" non-binary are females who are pre-teens, teenagers or very young adults.
(This doesn't mean most older people "identify as" "cisgender." The majority of adults do not have gender identities, ascribe to gender identity theory or use the phrasing "I identify as." Most adults simply know we are male or female and just say so plainly when the issue comes up. Most adults also do not use the phrase "assigned male/female at birth" to describe ourselves, our children or others. Because most adults know that human sex is a physical reality determined by genetics/nature very early on during development in utero, not an identity label signifying gender that parents and HCPs "assign" to babies at birth.)
I personally know a number young female people who "identify as" non-binary (and other newfangled "identities" such as vapogender and demisexual). Most of them are deeply unhappy, quite wet behind the ears and struggling with a host of psychological and social problems. Problems that stem from their own often troubled and traumatic personal and family histories, and from the misogyny of the larger culture, society and specific communities in which they have grown up. My heart goes out to them.
I don't believe that I am better than these youngsters. Nor do I believe that I am necessarily smarter. But I am far better informed than they are about the areas that are at issue here - sports policy and governance; sex discrimination; the physical differences between human males and females and their implications; the history of women's and girls' sports; the barriers that female people face and have faced historically because of our sex.
I also have a lot more - and a lot more varied - life experience in the "real world" than they do, and I am more savvy than they are when it comes to the law of unintended consequences.
Throughout history women with a lot of life experience, knowledge, wisdom and street smarts acquired in the school of hard knocks have been routinely vilified and dismissed, and our words of caution have been ignored. Unfortunately, sports governing organizations that are either run predominantly or solely by men (the male kind) have tended to make policy decisions about women's sports and female athletes without consulting many women (the female kind) with experience in sports and expertise in pertinent related areas. Indeed, many sports governing bodies have made a host of important policy decisions affecting female athletes without consulting any female people at all! This had led to some very poor policies that have proven to be very unfair to female athletes, and which have led to a lot of costly and time-consuming litigation. Yet here you are in 2022 advocating for more of the same and pretending that's what's best.