Stepping into the issue slightly, it becomes interesting. Ignoring the trans element, for now.
There's an interested debate here about parent's rights to choose how to parent. Now we as a civilization have decided that there are red lines that parents cannot cross. An extreme example: parents cannot beat their children as punishment. And there's a lot of not-quite-illegal things the government does a lot of education around, like drinking during pregnancy, in order to improve the quality of parenting and the quality of life for children. So government intervention in parenting is already, largely established -- at least when it comes to certain topics.
The government, however, does not intervene as parents take their kids to "Sunday School" and indoctrinate them (oops, my own experiences and biases are showing). And generally, parents are allowed full control over their children's lives unless they cross that red line. Few parents exhibit full control, micromanaging every aspect of their child's life, but they probably could and be in the clear, legally -- at least when the child is in their physical proximity.
Abstractly: schools, and specifically public schools, are not parents. They have to follow a set of rules set by society at large. And largely, aside from educating the students, they serve as a means to prepare students to become functioning members of that same society. This means that schools need to enforce some sort of public normalization on the students -- the exact form of which should reflect the society the students will enter, more or less. Optimally, they're preparing students for a society that will exist in the future, not the one that exists today, or one that existed in the past, but it's hard sometimes to know what that future will look like. You take some best guesses about this future society.
So now we have the conflict between the individual and the society. A parent yields some control when sending their kid to a public school, in the hopes that they will become a productive member of society. And this debate is about exactly how much control is yielded. And this debate is in many ways a core debate for our whole country - one of which can encompass residential schools, multiculturalism, religion, and more. Sometimes the guesses made about future society are off the mark, and what is intended to be a policy for good turns into a policy that was retrospectively harmful. We won't know until the future arrives.
But then the discussion gets completely overwhelmed by transphobic dogwhistling, and the resulting backlash, hiding the core of it.