Why oh why do they do it?
In the annals of science fiction there has been very little (almost none in fact) good comedy. I know the first reaction is going to be RED DWARF!!! shouted in a very loud voice and I'll grant you that and I'll give you Mork and Mindy and early seasons of Third Rock from the Sun and even Galaxy Quest, but that's it. Where's the rest?
Consider SUPERHERO MOVIE (consider it, but don't go and see it). It's not clever, it's not funny and it's the lowest form of cinematic wit, the spoof. This type of film hasn't been funny for a long time. Not through the Scary Movie franchise (which was so bad it really was scary), not through the Hot Shots and not through the Shriek if you remember the films that this movie is based on phase.
The truth is that science fiction does not make good comedy. Even the great Mel Brooks couldn't make it funny in Spaceballs!
On TV the recent examples Supernova and Hyperdrive were equally inept.
For me, possibly the three scariest words in the english language when put together are 'science', 'fiction' and 'comedy'.
So, until they learn to do it right let's all agree not to go and waste our cash, time or sanity on this stuff.