No, most fantasy stories aren't primarily about humans. Or at very least they aren't all just about humans with one token elf* lady thrown is as a love interest *(I mean sure, LOTR but the main cast wasn't all humans is what I'm getting at). Yes hetereosexuality is more common but why is it a male main character with a female interest instead of the other way round? Why can't some of the other characters who aren't love interests be women? Sure if we're talking about the past of course the lack of diversity makes sense because people then didn't think those people's stories were worth telling to the majority, and somehow they're still not important enough to even grace side characters? Even those this persecution is apparently over? How can both of these things simultaneously be true?
(you're entering stereotype territory)
There is both the stereotype that women like feminine things and the stereotype that women reject feminine things. I like the color pink and pastels and romance and cute things, am I a stereotype? I also used to pretend to hate the color pink and I didn't ever wear makeup and don't dress traditionally feminine, was I a stereotype then? I mean I still don't dress femininely or wear makeup, does that mean I've gotten over worrying about stereotypes and was I reacting to stereotypes before? What does that tell you about me? And what would your interpretation of me tell me about you? You see how layered this is?
Some people fit into stereotypes and some of those people reject them or embrace them. I've spoken to gay people that used to over embrace the super feminine stereotype of gayness because they felt obligated to, and others that rejected it completely because the last thing they ever wanted to be was another negative stereotype. There are stereotypes that say gamers are fat white males, how do you think an actual fat person feels about video games? Maybe they hide their interest because they're afraid of being a stereotype or maybe they embrace it even though they don't actually like games that much. What if they're also white? What if they're not? What if they're female? Or the stereotype that women who like video games are either sexy bimbos that are fake geeks or ugly real geeks. Do you think some ugly women might avoid games? What about a beautiful woman?
I'm not saying that you should reduce a character to a stereotype, you should never do that, but I am saying that for me, my character's relationship and feelings about the stereotypes that apply to them are important to me understanding my characters. Its because I want to avoid making making stereotypical caricatures that I consider these things in depth. It's hard to write characters that are vastly different from me but honestly I'd rather make mistakes and apologize and then get better at writing them then just never write a character that isn't my race, gender, religion and sexuality. It doesn't mean stories about characters like that are inherently bad but I feel like it robs me of plot and story opportunities. The stories I want to tell, and the stories I want to read involve these things.
*edited for clarity