Don't know if this is intentional or not, or maybe just a bug, but there's a slight screen blur over everything when aiming, not just the highlighted sky part.
There's no blur of any kind when not using eye focus or using it.

I get that gun is supposed to be blurry, because depth of field and focus, but is the blurriness of everything else intentional?

It's a really minor thing, but it's noticeable