I personally don't necessarily think that it's child abuse (though I certainly won't argue that it isn't), but I ultimately agree with your sentiments. Personally I would like there to be more studies done into gender dismorphia in children, there potentially may be some more 'objective' criteria that could be used to better understand when it's say a child confused, curious, or just experimenting and when it's legitimately a physical condition. I've heard that it's easier to transition if you're before puberty, which does make sense if you ask me, but conversely without some 'objective' criteria for telling when a child is transgender and when they're just being a child I ultimately feel that more harm than good would come out of letting children transition. But those are just my thoughts.