Like parent said, it's low-light in the visible spectrum, but I'd totally expect these vehicles to scatter tons of light in non-visible spectrums, making these conditions well-lit in those spectrums. Like a bat using echolocation.
I think the point GP was making is that an attentive human driver may have been able to see the pedestrian much earlier than when she becomes visible on the video.
this, the human visual system adapts to darkness. Consider that the victim who obviously is crossing the street as part of their lifestyle has likely done this many times before, and of all the vehicles that could have hit the victim, the one that did happened to be one of uber's self-driving vehicles with a clearly inattentive driver behind the wheel. A driver paying attention to the road would have at least hit the brakes well before impact.
Intermittent street lights reduce the adaptation though and add glare - the human visual range for scotopic ('dark adapted') and mesopic (twilight conditions) vision is about 4 orders of magnitude of luminance (cd/m²) that the retina can perceive simulataneously from 0 to saturation, without adaptation (dilating pupil). Dark to light adaptation is very rapid and happens in fractions of a second, light to dark adaptation happens over minutes.
The eye will adapt to a mean level of light in the larger FOV (not fovea only) - that is why instrument clusters on cars need to be low-level lit, to not disturb this adaptation. Exterior light sources like headlights and street lights further influence adaptation and veiling glare can lead to light sources overshadowing smaller luminance signals and pushing them out of the range that the eye is adapted for.
