The truth is that Trout, like Vonnegut and Ray Bradbury and many others, writes parables. These are set in frames which have become called, for no good reason, science fiction. A better generic term would be 'future fairy tales'. And even this is objectionable, since many science fiction stories take place in the present or the past, far and near.
Philip José Farmer
fairy-tale, genre, kurt-vonnegut, parable, ray-bradbury, science-fiction