Kinda, though all the mixed-sex couples that are canon are couples here too, I just don't focus on them. Also, as far as my research goes (by looking through the pony wiki pages), there's a lot more male characters than we notice, since they are mostly in the background.
(rolls eyes) Oh sure, gays and lesbians get persecuted, imprisoned, tortured, and killed in all SORTS of NASTY WAYS for the past 10,000 years or so and when they finally get some time in the sun (on the internet in a make believe world at least) people start screaming that they don't want to see it. You know what, DEAL WITH IT! It's HER COMIC and if she wants lesbians then your gonna GET lesbians for BREAKFAST BOY!