Now, I'm no expert here (god help me if I were), but from the stories I've read from those that have gone through with detransitioning, the Trans Community™ is very violent to those who express regret at their decision to mutilate their genitals or pump themselves full of the wrong hormones because that goes against their rosy picture of how transitioning is very important medical care, and not just a bunch of wannabe Mengeles trying to play God. When you're being bullied constantly whenever you express even a slight hint of disappointment, it doesn't seem surprising to me that a very small number of people in this study actually felt comfortable coming forward with their regrets. Let's not forget those that 47% themselves instead of opting for the long and painful process of trying to undo the damage that's been done.
Obviously, the solution is to be like John and find a rich paypig to buy you tons of useless crap that will distract you from the huge mistake you've made. It's so simple, troons!