You have been told repeatedly by others exactly who your behaviour is hurting. As such, I find it hard to believe that your question here is genuine and in good faith.
It appears that you have somehow conflated freedom and respect of transgender people with sterilisation. This is an interesting insight into your mind. First, just because a person is a child doesn't mean they do not deserve to be treated with respect, and just because you do not understand their feelings does not make them unworthy of respect. Second, not all transgender people wish for physical treatment, and not all physical treatments result in sterility. Some may result in sterility, but it is not a defining factor. You are essentially saying that adolescents must keep their sense of smell in tact – and as such we cannot remove wisdom teeth. Loss of sense of smell is, of course, a risk involved in major oral surgery, but the reason we remove our wisdom teeth is not to lose our sense of smell.
You are correct that people must be aware of the risks involved in any treatment, as these are large decisions. All people, children or not, need a long time to make these decisions. But prepubescent children are in the unique position that they may delay puberty, buying themselves more time to be certain of the consequences with fairly little risk. This is by no means sterilisation.
I do not understand what you mean by "lying to children's parents" or "hiding the whole dirty business". What exactly is hidden, and what has been lied about? I think you are using deliberately inflammatory words which are not quite true ("lying") to incite an emotional response. Is this deliberate or accidental?