Yes, sometimes kids go through silly phases, but the research has been done and if providers are properly trained, gender dysphoria can be reliably differentiated from other issues. I’m sure there are optimizations that could be made to the process- the article discusses debate over the ideal timing of puberty blockers, for instance- but it is solidly established that transgender kids exist and benefit from transitioning.
Conversion therapy and hoping they grow out of it do not help- hell, “do not help” is the *best case* for these options. Transition does. More pediatricians, parents, and everyone who is involved in child care need to know about this. Even if not enough to diagnose it on their own, at least enough to know that it’s possible and worth calling a doctor(or specialist doctor, if already a doctor) if a child in their care starts showing signs.