There is basically three places to set a Sci-Fi show, on a Planet, on a Starship or on a Space Station, Star Trek had already down the starship twice so it was perhaps only natural they would want to try something different.
Now as for similarites Hollywood often turns out films with broadly similar plots
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Why can't the same hold true for TV shows?
I would suggest that it does. Most of the 'coincidences' involved in studios releasing alarmingly similar flicks at the same time is a result of attempts to cash in on other people's ideas. Whilst I've only ever done work at the bottom end of the movie business I have sat in meetings and seen this sort of thing commissioned based precisely on that strategy.
It's not just a space station setting though is it. It's also the decision to suddenly do an extended narrative over multiple seasons with soap opera style character development. This was totally unlike what Star Trek had done before (or would do again thankfully). It's also the fact that the major storyline turns out to be a major war with a mysterious unknown enemy. That's a lot of coincidences to happen at the same time.
I've seen much worse rip offs but its hard to avoid the conclusion that the basic concept was being lifted. In the details the shows are very different, but in basic concept its a bit too convenient to be written off as coincidence.
nicely done!
