I think the hurdles of queer love are just more interesting and fresh. You can't rely on all the gendered romance tropes of straight love, and while being of the same gender has its own tropes, they aren't as cliche by virtue of being queer.
I'm so used to seeing strong breadwinner man + submissive stay-at-home wife, it's nice seeing representation of more balanced relationships. There's just something about people being so similar to each other that makes it feel better to me. It's possible to do that with straight stories, but I've never seen it, whereas queer stories seem to default to it.