You can be gay. Try actually playing this game.
You can be bisexual, not gay.
But you already knew that.
In any case, this is just one more example of why having a voiced protagonist with a longer backstory is bad for Bethesda games because their uniqueness was in giving us a blank slate to build our own character, something that most other games do not allow us to do.
I wouldn't be surprised to learn Elder Scrolls VI has only one race to choose from and it comes with its own backstory because "previous games did not allow Bethesda to tell the story they wanted to tell" as I believe Todd Howard put it when explaining the reasoning behind the voiced protagonist with a longer backstory.