Of course. But who should make that determination? You? Religion? Government? I’m in favor of letting families make those decisions pursuant to the best medical knowledge available - just like they do for every complex decision. For one child it might be appropriate at 9, for another 13, for another 16. Not my business - or yours.
NO ONE KNOWS how an individual's GD will resolve (or not), until after puberty. NO ONE.
So when a GD kid is put on drugs prematurely all we have is a BIG MAYBE:
1 - MAYBE that kid would have retained their GD through puberty, and MAYBE GAC drugs would have helped.
2 - MAYBE that kid would have gone thru puberty and simply discovered that they were gay.
So how many gay kid's lives are you will to destroy based on those MAYBEs ??
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Now I understand that if we had a crystal ball, and we could definitely determine how a kid would emerge from puberty and adolescence, trans or not, then I understand that - in some ways - it's preferable to start a trans kid on drugs early. But NO ONE has such a crystal ball.
In addition, trans activists have been very effective in promoting the idea that these drugs are safe and reversible. They are not!
This lack of transparency is telling.
And finally, OTOH you think gender is fluid, but on the other hand you support irreversible interventions on kids? What if they would have later decided that their earlier sense of gender had altered??