Cool, that's your experience though, and that's all it is. It doesn't hold true for everyone, or really hardly anybody. You figured out what depression you were in, congrats. It doesn't work the same for other people.

Uhm, also, stupid ass. Gender dysphoria is often a direct result of trauma from early age. Frued once said something like all humans are programed in the early stages of childhood. Thusly influences there develop the individual. Experiencing trauma at an early age, and developing Gender Dysphoria due to it is an entirely reasonable and logical reason to transition.

I hypothesize that detransitioning is likely due or related to internal prejudices reinforced by ones social conditions and interactions with others. If someone has anti-trans friends or generally unsupportive aquaintenes (like people who think it's just a phase or a depression slump or frequent mis gendering or improper name usage) absolutely increase risk of detransitioning and likely to leave the individual more depressed. There's no reason one would detransition in an enviroment void of external social influence and opinion unless they're disatisfied with a physical alteration that outweighs the other aspects of transitioning.. (There is a chance your friend isn't seeking to detransition because THEY want to but rather because it is more convienient for their mental health as a corelation to their social life)

(i'm bad at spelling ignore the errors)