No kid will get "castrated" just to fit in. Actual gender change operations aren't even done until adulthood, only puberty blockers are sometimes used which are reversible. And only if the child's dysphoria is so extreme it really impacts their quality of life or endangers them (think self-harm). In this sense it's entirely "for the children".
Also 99% of trans people have no regrets. The system works. I think it's amazing that we live in a world where people can decide their own life and body. And I don't really get the whole hate against trans people. It's not like they're harming anyone.