If we agree on the effects of estrogen, then I don't think data is needed. This is a situation where I can simply use common sense (unless you disagree, then sure, I'd have to provide data)
A) we don't. Estrogen in no way reverses the effects of male puberty. Men on estrogen are still not women, nor physically equivalent.
B) it's irrelevant. Stevie wants the conversation to be based on risk, but women aren't constrained by What Stevie Wants. We don't give a crap about his preferred framing of Why Stevie Gets Things Other Men Don't. He was male because his father's sperm carried a Y chromosome and nothing short of time travel can change that.
C) his vapid arguments aren't worthy of respect in a democratic society. They are just self justifying bilge he is sprouting to try and shore up his claim that he qualifies as a woman. The Supreme Court has been VERY clear. As has hundreds of thousands of years of evolution.