Oh boy, this is going to be a long topic that will make my fingers hurt.
I think because this person is so far removed from you, it's best not to judge. I know many female bodied folks who never wanted breasts, bound and did everything to hide them. Some were trans, some were not. All had issues with cat calls and the unwanted attention their bodies attracted. I can identify with that!
For myself I am not my body, even though I present as a white straight dude, that is not my identity. I really don't give a flying F about my 'gender' I don't feel 'manly' and am far from the social norm in identity, I also have a couple of 'mental health diagnosis's. Interestingly enough gender 'divergence' is very common with folks who share the same traits that I do.
I think Will's best interest is loving support and acceptance.
The tricky part is puberty blockers, and body augmentation. Perhaps if they felt supported in who they feel they are, in a holistic way body augmentation could wait until they are and adult. BUT do know many trans folks who are not supported do NOT LIVE to adulthood.
Gender identity is one thing, sexuality is another, sexual preference is different than the previous two. I cannot speak for others, only for myself, but I really don't care whats between my legs nor where I choose to shave. I do have two kids, and my partner has all the parts to make the little buggers, thats really where it ends in my family.