Turning off shadows fixed this. Setting shadows to any setting above 'standard' fixed this. Check out the 3 images below. Two separate images & one image with both side by side.
Take out the option for 'standard' shadows. Because it looks terrible, not just the shadows, but causing textures to appear like that. Or maybe there's a better way to apply the 'standard' shadow map filter within this game?
"I've ultra textures but 'standard' shadows COMPLETELY ruins them because of the shadow map filter for 'standard' shadows." - Who, outside of programmers are going to think like that? Certainly not your average gamer.
"I'd better set my shadows above 'standard' or disable them so my ULTRA textures aren't atrociously ruined..." - Yeah, your average Arma3 players doesn't think like that.
We're not going to be thinking about how shadow map filters are applied while setting our shadow quality.