EDIT: so, known bug. Fix is coming. ONLY happens when you use non-native resolution. Sorry for bad info below. Just reminded me a lot of the fact that there is some intentional movement in this screen and I thought that was a bug.
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So, this is by design. I actually flagged this as a bug when I first started working on the game. But it's meant to work this way. It should happen regardless of screen resolution.
In terms of the "why," the Designer who implemented said that it actually "feels" more natural to have the UI respond to your directional input. Like, if you think of the game's history and roots in Titanfall, a lot of the HUD stuff comes from having that perspective of being inside of a Titan or inside of a Pilot helmet. So your HUD is going to move a bit as you move.
It still kind of weirds me out, but I can confirm it's entirely intentional.