Part of me feels like we need to just make cars much much much more reflective (being careful to not have hard corners or flat surfaces that could create glare during the day). First of all, that would make them much more easily visible at night (which would be great, and is something everyone should want)... but it would also mean that if you are an asshole and use your high beams or otherwise shine a light at a car…
How about other approach - trying to foster a culture amongst people of not being an a-hole to others, especially on the roads? Rather than playing whack-a-mole with all possible variants how assholism can be manifested. It generally works quite well in western Europe, I can't remember the last time somebody blinded me (if I don't count split-second situations of popping up suddenly from behind some tight curve).