Of active craft, yes. I had to double check; I became suspicious when I saw nothing Russian, but indeed there are no active Russian probes.

In the sense of whether it is everything ever launched . . . not even close. It might be an accurate representation of those probes that are still active and in contact with Earth.

Their site says it's a catalog of "the active human-made machines that freckle our solar system and dot our galaxy." Obviously it's not really the "galaxy," per se, considering we only have one probe that's actually left the solar system so far (Voyager 1). There are a number of inactive probes.