What makes you think this isn't being done? The bulk of evidence is that the regret rate is quite low and totally acceptable compared to the downsides of not allowing trans affirming care.
Evidence?
Perhaps you're buying into the unsupported assumption by anti-trans activists that trans affirming care is being administered recklessly and without much safeguarding or care.
And you're buying into the unsupported assumption by pro-trans activists that hormonal and medical intervention is the perfect solution to any and all mental health issues, and that questioning whether that makes sense is bigotry that shouldn't be allowed.
Seriously though. You seem to have swallowed two misrepresentations. First, the claim that "affirming care" is being administered in a reasonable, well considered, well informed, and thorough fashion.
That one is not true. It's not true by way of personal experience, and by way of the policies in place at Planned Parenthood in many locations - where they will provide a prescription for cross sex hormones on the first visit unless there's a medical condition that would prohibit it (eg, they won't prescribe estrogen to a male with epilepsy, it's counter indicated as it lowers seizure thresholds).
Secondly, you also seem to have swallowed the claim that "regret" is extremely low. Right now, regret is growing. One of the problems with many of the surveys cited that say regret is very low and that detransition is driven by social pressure is that they're
only asking people who still identify as trans. By the very design of the surveys themselves, they exclude the very people who detranstion - those who were misdiagnosed as transgender, and who no longer see themselves as trans at all. It excludes exactly the group of people who are the biggest concern when it comes to the enthusiastic administration of "affirming" medical care.
Take Chloe Cole's own example of taking years of slowly escalating trans affirming care, by no means rushed. Diagnosed with gender dysphoria at 9, socially transitions at 12, begins puberty blockers and hormone treatment at 13, and surgery at 15. hardly a gallop.
Not a gallop, but also entirely irresponsible! Doctors shouldn't be taking the word of a 9 year old when it comes to this sort of thing. And they should NEVER be ******* up a developing person's body at the onset of puberty. They sure as hell shouldn't be performing surgeries that aren't medically necessary on bodies that aren't even fully grown!