There are 2 issues here, which you seem to be confusing.
- Should people who are trans be treated with respect and given appropriate treatment? (I think most people would argue yes)
- Should children who have symptoms of being trans but actually these symptoms are the result of some other cause, be incorrectly treated and given life altering and irreversible surgery or hormones?
(I think most people would argue no)
The question is how do you know whether the 1000 per cent increase in girls saying they are boys are actually trans or not? That is a massive increase, and the question at least needs to be asked if these girls are actually trans or not. That answer may be yes, but any responsible adult involved with the child should be open to the answer being "no, there are other reasons why they are presenting with these symptoms".
If your child presents at the hospital with symptoms of a broken leg, they will xray your child to find out if they actually do have a broken leg and decide how best to treat it. They don't just pop any old sore leg into a plaster cast without proper investigation. And they will always tell the parents what they are doing because the parents need to be there to support their child.
Just as a general rule, anyone who is encouraging a child to keep secrets from their parents has to be viewed with suspicion, even if that suspicion is later allayed.