I guess some examples I can take from off the top of my head:
"He has luck with all the females"
"Females are better/worse at x"
"I accept I will never have female companionship, I am too ugly"
"Of course a female wouldn't like x because of y reason"
(This is in no way an extensive or complete list.)
It just sounds so.. odd. I understand they're synonyms, but it carries a different tone that seems very odd to me?
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It's not anywhere close to an issue, nor am i trying to make it one. It's simply a trend I've been noticing that I think is a tad odd and I wanted to get a better understanding of the thoughts behind it, so that I could feel not as confused and creeped out by it.