let's be objective here....if they're blinding you during the day, when the ambient light far far far outweighs the amount of light output by even the brightest xenons thus your pupils are adjusted and only let in a small amount of light, how on earth do you not crash and burn at the first site of a headlight at night, when your pupils are adjusted to very minimal ambient light thus the exposure is MUCH higher to your retina...
Well I'm on about that evening hour where it is actually darker, but most people don't require lights to see the road ahead of them, sidelights are good because other drivers and pedestrians can notice other cars quicker, but dipped lights in certain conditions are too bright and if you work in the car for hours in the evening this gets irritating and affects your eyesight.
Everyones eyesight is different so you know its not black and white.