Why do some people still say transgenderism is a mental illness?

World Health Organization removed being transgender from the mental illness list many years ago

Updates
8 mo
In 2023 currently and I have seen more than one user called transgender people “mentally ill” on this website before I posted this question

Transgender got removed from the mental illness list by WHO (world health organisation) in 2018 or 2019 I believe
Why do some people still say transgenderism is a mental illness?
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