"Reversible" obviously-- obviously-- doesn't mean you can go back in time to undo the decision. It means you can undo the effects afterwards to a degree.That is not a concession, that is my point. You've taken the position that one option is permanent and the other is reversible, and neither option is reversible. Decision permanence can be argued either direction, hence, it's a wash. Even if we pretend that employing literally the same procedure as the chemical castration (pioneered by John Money for use with pedophiles) actually has no long term effects, the years of what their life would have been are gone permanently, along with all the formative experiences that would have been.
That degree is not 100% in either case. But it's much closer and easier with hormonal blockers than puberty.
So the "time" argument applies equally in both cases. But the ability to mitigate/ reverse the effects after that time applies far more in one case than the other.