Take a cis boy and raise them as a girl and you’ll see quickly how much their quality of life is improved by letting them transition to be a man. It is probably obvious to most people that this is true - the only reason studies like this continue to seem relevant (and not as obvious as stating giving water to people suffering from dehydration promotes their well-being) is because society has such a hard time accepting trans people can exist, that someone can be born “in the wrong body” and need gender affirming care that goes against their perceived sex. That’s it - it’s an educational and cultural problem born of ignorance (and a lack of tolerance for gendered difference that, let’s be honest, is more of a problem in nations influenced by Christianity).