WoH is realistic in the sense of pure science, but it's way off in the world view.
The scenario posed by Planetes is totally realistic. The debris collection is just the lead for the main plot of the story, which is the conflict in space development between first and third world and the space terrorist fight for equality between nations. The science part of Planetes is good, but what make me totally fell for the show is the depth of the social issue it brought up in space exploration. It follow classic sci-fi tradition by asking lots of "what if" questions. It's not an average so-call sci-fi show which is merely an advanture drama or fantasy story loaded up hi-tech props.
In response to ewilen, even Planetes is set at year 2075, collecting space debris may still be too much of a work for a robot. You gota see the show to understand what I say. Let me give you an example from the show. In the first eposide, the debris team have to attach a rocket to a space debris to push the debris back to earth in order for it to burn up in the atomsphere. I don't think a robot can handle this job in merely 70 years.
The background of Planetes is not just space tourism, rather it potrait a world in which earth had runs out of natural resources. The only place to turn for more resources is space. Mining in moon and mars is the major driving force of space exploration.