I still think you do not understand it. The motion blur also happens in real life when you manage to somehow pan your vision while preventing your eyes focal point without anchoring to static locations. The only difference is that the theoretical framerate and therefore shutter speed of eyes is much higher than average camera. But you can still easily observe even non rotational motion blur, for example observing neighboring train tracks when traveling in a moving train. That makes it very easy to observe motion blur with your own eyes, since they will most often focus on some highlight which appears static under such speed.
Your eyes are nothing more than a pair of biological cameras. Furthermore, you constantly keep bringing up your subjective bad experience with motion blur, which just reinforces my point. You have such a bad experience because you’ve experienced mostly games that utilized it wrong, and as a UE4 developer you have also been using it wrong in the engine ever since you started using it, because the Target FPS value was added only recently, and with a wrong default value on top of that.
It’s like if you were saying that all food sucks and is bad, because it makes you feel bad, unhealth and fat, while you’ve been eating nothing else than McDonalds burgers, snickers bars and coca cola all your life.