Very few young people who access gender-affirming medical care go on to regret it
A large majority of young people who access medical gender-affirming care including puberty-blockers and hormones say they are satisfied with their choice a few years later, according to international research
From what I understand, a lot of studies go on to show that this is one of the main reasons for regret. It's not "well I wasn't actually trans" like a lot of people like to think, a lot of people de-transition simply because presenting as your AGAB is far easier in a lot of places.
I am sick right now and can't be arsed to look up the study I saw, but I am pretty sure it was American trans people who transitioned who were tracked. From what I remember, like 5% detransitioned, but when they dug into their reasons, the vast majority of them did so for reasons other than regret at having done so. Their reasons were social, financial, etc. Only half a percent came back and said they weren't trans. One in 200.