I imagine that the ordered sort of structures ( crystaline ) that you need to get electrical superconductivity are not present in bulk out there in outer space.
there is a phase of the quark gluon plasma that is color superconducting,
this state of matter would only have existed at very early times in the universe or in collapsed star cores. I am not an expert on nuclear physics so i don't know how solid this prediction is , but ... then again this isn't really electrical superconductivity either.