This is an odd argument, especially when considering the modern movement of equality. Everyone is equal, right? The way children who don’t learn quickly are treated has changed dramatically since I was in school. To be associated with prejudice or racism is a political death sentence. We are a society that believes, or at least claims to believe because to do otherwise would be rude, that all people are created equally.
The problem for those who want to make this claim and who also want to claim that Christianity has had no major, positive impact on society simply can’t have it both ways. Where else, if not from Christianity, does the idea of inherent human worth come from? People obviously are not equal empirically. Some are smarter, some are faster, some are… better by every measurement. Where does this notion of universal equality come from?
Mark Shea does an excellent job of explaining the roots of human equality and where it originated. His short article is worth a read in detail.
But the thing to note is that it [gender equality] owes its genesis entirely to the Judeo-Christian tradition, even when it is rooted in reaction to and rejection of that tradition. All you need do is compare Western notions of gender equality with… well, what? There’s nothing else out there. The dim and flickering attempts at asserting gender equality in Islamic or pagan societies are restatements of western assertions that trace back to Christianity and nothing else.