Tried this again and realized this only happens when I custom increase the resolution beyond your HD profile, so I think your profile was fine to begin with. The black bar gets larger the higher I set the resolution (its very small at 2300x res and very noticeable at 2700x res).
So I think its probably not a bug in QGO itself. Seems like something the developers might have natively implemented in the game for some reason, they dynamically cut off the FOV depending on performance I guess?