And why are every companion bisexual? It wasn't the case in other D&D game. Most character were either attracted to one or the other gender, both was very rare and more like, with beamdog companion, not originals one. I'm totally fine with pansexual character, just, not all of them, or is it the new culture in D&D?
It gives the player more choice, letting you romance the one you choose rather than the one effectively chosen for you.