It is very one-sided. I was a tomboy the entire time at primary school. I didn’t get the other girls, had no interest in dolls, only wore jeans and asked for meccano sets for Christmas.
I wasn’t ‘trans’, I was just a child. Like 80-90% of gender non-conforming children, my issues were resolved at puberty.
www.frontiersin.org/articles/10.3389/fpsyt.2021.632784/full
Some children persist, and for them an early transition may be beneficial, but if there is medication involved things become dangerous.
Early medical transition and your body never goes through a normal puberty. We know that makes the children infertile, and may well also impact on their brain development. There needs to be research on this, but transactivists seem to block research.