"Should" is a word that ought to be banned from this sort of discussion.

It's illegal in this country—the UK—to drive at night without lights. Doesn't stop it happening, though. Either someone forgets to turn the lights on, if they're manually controlled, or they actively turn them off because the UI is ambiguous (this happened to me, once), or the filament bulb burns out (again: filament bulbs are/were mandatory in the UK, originally to rule out carbide lamps without actually banning them), or there's a wiring/software fault.

The point is, vehicle safety measures should be fail-safe, and driving an invisible vehicle at night and relying on lights to make yourself seen is kind of the opposite of that.

That’s true. But I’ve found on a couple occasions that I couldn’t see a car in my mirror when driving at night because it was very dark colored and its headlights were hidden by my b-pillar.

This sort of thing wouldn’t happen much when headlights sprayed widely, but newer focused headlights are harder to see from the side.

Even if there are lights it still makes it harder to see, which is more dangerous.