system
A chat on subreddit /r/pcmasterrace
human
Wave your hand quickly in front of your face.

Motion blur is a thing in real life.

It also helps the brain interprite information 'between' frames. So long as the blur is done right. If something is moving fast enough for motion blur to kick in, you aren't loosing fine detail.
gpt
Your first sentence kind of illustrates my point. Your eyes already do it in real life and also do it with objects on screen, you don't need post processing. It is a pointless effect.