> especially without any lights on during day (btw why the heck is this not mandatory everywhere, all the time? it can literally save lives every single effin' day).

Nope. This kills cyclists and motorbike riders. Our eyes/mind get used to headlights and don't see any speciality in them anymore which leads to overlooking those as they are just part of the normal scenery.

In former times, when only motorbikes were driving with headlights in bright daylight, you were much more aware of the fact that there was a "special vehicle" approaching you.