Kids should not be determining life long changes to their own bodies.
Sounds like common sense to me. If an adult wants to do that, they should be free to do it. Kids are retarded and have no concept of future planning. The way most people feel about issues when they were kids into their teens does not hold into adulthood.
They can always change their mind. Sort of like they'd do if they're forced to pretend to be straight and then decide to be gay later on.
If they are taking "puberty blockers" or even more extreme actually complete a sex transition, that shyt is a little more permanent obviously. On puberty blockers:
GnRH analogues are reversible. Cessation of them usually results in patients restarting their genetically intended puberty within six months. Although the treatments are considered safe, they are not risk-free. Most transgenders become infertile as a result of the hormonal switching medications.
A child should not be able to be the sole decider in doing this. I don't even think it should be allowed unless medically necessary. As they said in the video and most of them agree, a "lets wait and see" approach is best.