Why do you think it is bad to allow people to self-identify as a different gender?

There are many more historically attested genders, as one can see on the

Among many Indigenous societies, two prominent features often distinguish the lives and social roles of third gender persons from those of cisgender persons or contemporary transgender persons in non-Indigenous societies. The first is that many Indigenous terms for third gender people contain both the word for “man” and “woman” in their construction, and that third gender people are seen as embodying both of those genders in diverse ways. The second is that the history of many third genders is in the community role of religious specialists, which also takes diverse forms, depending on the beliefs of diverse cultures. While not all third gender persons are defined in these terms, across our species, this phenomenon of the third gender religious specialist, healer, or spiritual worker has been part of our collective identity and human experience since time immemorial."

PBS has a page regarding gender variance worldwide. It says in part:

Do you enjoy cheating on your spouse? If so, why?

Even after the end of the modern era and as the colonial period wanes, hundreds of distinct Indigenous societies around the globe still retain their own long-established traditions for third, fourth, fifth, or more genders. The subject of Two Spirits Fred Martinez, was not a boy who wanted to be a girl, but both a boy and a girl—an identity his Diné culture recognized and revered as nádleehí. Meanwhile, Hina of Kumu Hina is part of a native Hawaiian culture that has traditionally revered and respected mahu, those who embody both male and female spirit. And Japanese-Samoan fa’afafine artist Yuki Kihara participates in major global cultural events, functioning not just as representatives of their gender-based community, but of their nation. Kihara had both a solo exhibit at the Metropolitan Museum of Art in New York and represented New Zealand at the 2021 Venice Biennale.

I personally don't. What other people do with their lives is none of my business. It doesn't harm me in any fashion.

World Gender Customs map

Measles confirmed in Colorado Springs, public asked to watch for symptoms - KKTV

People currently take umbrage at the idea because they think it's a novel fad, "done to get attention." Nothing could be further from the truth. Gender variance has always been part of humanity.

"Throughout recorded history and since time immemorial, thriving cultures have recognized, revered, and integrated more than two genders. Terms such as transgender, gay, or bisexual are Western constructs that assume three things: that there are only two sexes (male/female), as many as three sexualities (gay/straight/bisexual), and only two genders (man/woman).

It’s not uncommon for third gender people to perform critical spiritual and religious functions in their communities.

Why cant a narcissist admit when they are wrong?