Nobody (serious) is saying that. First, when this is talked about, it's always about averages, which are meaningless from individual perspective.
Second, there are obvious biological traits where women are less capable than men on average, like weightlifting. There are also traits where women are more capable, like having kids.
These are facts though. You might also not be a fan of idea that "Earth revolves around Sun", but that's how it is.
On the other hand, I can understand your feeling. I am for example not a fan of idea that many humans are xenophobes.
