> Its a historical thing which is gradually falling out of use.
No, not at all. Different sexes present themselves differently in every culture and therefore in every language. If you only learn from one sex, you won't be able to tell what parts of their language are sex-specific, and you'll learn to speak like they do.
I've gotten this criticism without speaking at all, by texting with people on Wechat. One girl remarked to me that saying 嗯嗯 [it's an agreement noise; very close in concept to "uh-huh"], with two syllables, came off as overtly feminine. As a man I guess I'm supposed to text 嗯.
I still use 嗯嗯, though, because it's as common as dirt in my experience and 嗯 is much rarer. Is that an artifact of my pool of conversational partners? Probably.