Here's a thought: If at least some Steampunk is set in the universe as the Victorians thought it was -- Moon with an atmosphere, "Luminiferous aether," etc. is there room for a sub-genre in the universe we thought we had immediately after WWII? Venus as a swamp, Mars as an old, but habitable desert, etc.?
Granted, it didn't last long, though it lasted longer in fiction -- where genre conventions kept much of the solar system "warm and earth-like" long past the point where scientists knew that just wasn't true. But did it last long enough to create a compelling world view?
Or would an author attempting that today just look like somebody who couldn't get their facts straight?