I doubt it's class based. I'm guessing it had nothing to do with the smuggler class in the case of the republic side, just the writer decided she was a bit more open. I can however, confirm that Cytharat is not bi because the writer specifically said he was proud to have written him gay rather than bi on Twitter.
Gaaah...this actually made me think they should just make that a Smuggler class feature!
Smuggler Snuggler: The Smuggler can flirt their way into anyones heart.
Of course, I'm sure I'm the only one to find that to be a good idea.