> Identifying strength as solely being a 'manly' attribute is pretty sexist.
No, you're missing this completely.
Let me try something different, but analogous. Back when I was in high school, I ran track. My sister (in 8th grade at the time) was fast enough to have been 4th on the men's varsity team. So people told her, wow, you're as good as a guy! Did we value speed as a "solely" male attribute? No, it was valued separately in its own classification (men and women race separately). However, the fact that my sister was good enough to actually compete with the men (who are overall much faster than women), came across as a compliment.
I would go so far as to invoke "isomorphic" as the most apt term in describing the type of compliment involved in mine and scrapcode's scenarios.
> Taking attributes and ascribing them to gender is useless at best.
Useless at best? I see this phrase a lot on the internet lately, and it must be a fad because it wasn't in popular usage a few years ago.
Men and women have different traits. It is a completely, scientifically, undeniable fact. Men will be better at certain skills, and women will be better at other skills. The latest social trend cannot change that.
If a woman is good enough to play in the NFL, great for her, we'd all be glad to see that! But that doesn't change the fact that the odds are ridiculously stacked against her being capable of doing such a thing. Maybe start a separate women's NFL? Alright, but since no one's done that, let's use common sense and say football is a man's sport. What is an activity that's typically only associated with females only: ballet dancers. Sure, there are male ballet dancers but until the ratio is close to 50/50, the term "ballet dancer" will continue to be associated with females, and for good reason.