I find a lot of the time is that its not that lights are brighter, its that they have their lights set too high.

I was wondering why people were flashing  me one night and found that after a service, the mechanics had set everything to maximum/high, and that my headlight angle was at its most level, therefore blinding drivers. I quickly adjusted it back to a safe level. 

People think having the angle set high as possible is safer as the light goes further, which it does to a degree, but blinds others.