Emergency vehicles are the absolute worst; not the headlights, but the emergency lights. They need a dim setting that allows drivers approaching an emergency scene to see and avoid it.
I know a guy who supplies Emergency lighting to police and fire departments. He told me that there’s some research showing a direct correlation between multiple bright flashers and collisions of stopped emergency vehicles.
Cop cars used to have one or two flashers, now they have over 20.
The eye is drawn to light and the steering wheel follows.
That said I’m thinking of switching to brighter LED’s. What I’d really like is for regular headlights to be dimmer and brights to light up a stadium.