People are different, we group and categorize these differences in all sorts of ways. A lot of these differences are going to impact who we are, in those ways we prefer to consider beyond the scope of physiology.
This, in itself, isn't unethical to express. It isn't factually disputable, either, but there's still a legitimate ethical concern. This can lead to bigoted ways of thinking, cherry picking of facts and dismissal of context, to form prejudices.
There are a couple layers to this issue, but right off the top, acknowledging these differences in the aggregate is not the same as making a generalization. It isn't a justification for condemning deviance from an average. It isn't about getting anyone to conform to standards. That's a leap some immediately jump to, but there's no rational reason for it. A genetic reason, maybe, but that isn't a reason for our thinking to be restricted by it.
Another issue is that there are no objective values that can be assigned to these differences. A hormone might be higher in one person than another, but that isn't better or worse. Either way, it's going to come with some advantages, some disadvantages. It's just one element in a myriad of other differences, none of which can be given definitive value.
This fuzziness makes it all too easy for people to focus on a positive element on one side, and contrast it with what seems to be a negative on the other, to support a narrow-minded bias, which of course, just happens to favor themselves.
I don't believe we should let that sort of stupidity steer us away from factual discourse and study, but it is something to be conscientious and ever vigilant of.