The full study link is here, and open source, so anyone can read it. The abstract summarizes all the most important points. Not only do the vast majority of young adolescents grow out of this, strongly indicating it is a phase, but it is also associated with poor mental health. This wasn't some small study. It followed thousands of individuals over a 20-year period:
Adolescence is an important period for the development of gender identity. We studied the development of gender non-contentedness, i.e., unhappiness with being the gender aligned with one’s sex, from early adolescence to young adulthood, and its association with self-concept, behavioral and...
link.springer.com
Gender dysphoria is a sign of mental and emotional instability, and should not be encouraged. It should definitely NOT be accommodated with actions that are potentially permanently harmful such as hormone treatments, or worst of all, invasive surgeries. Sometimes protecting minors means protecting them from their own impulses.