This gets to a gaming rant of mine: Our natural vision can handle these things because our eyes scan sections of the scene with constant adjustment (light-level, focus) while our brain is compositing it together into what feels like a single moment.
However certain effects in games (i.e. "HDR" and Depth of Field) instead reduce the fidelity of the experience. These features limp along only while our gaze is aimed at the exact spot the software expects. If you glance anywhere else around the scene, you instead percieve an unrealistically wrong coloration or blur that frustratingly persists no matter how much you squint. These problems will remain until gaze-tracking support becomes standard.
So ultimately these features reduce the realism of the experience. They make it less like being there and more like you're watching a second-hand movie recorded on flawed video-cameras. This distinction is even clearer if you consider cases where "film grain" is added.