In Germany a completely black traffic light has no meaning, rules are as if it wasn't there. Most traffic lights have the usual signs for priority roads for this situation.

But a broken traffic light is a situation that is unfamiliar to drivers, and at peak hours the crossing is guaranteed to be either difficult to navigate or to have suboptimal traffic patterns (otherwise there would be no traffic light in the first place). And of course pedestrians have to improvise (and Germany has a lot of pedestrians compared to the US)