No one really means it. Indeed, a call for subversion and rebelliousness tends to be more rigorous and prescriptive than most calls for anything in literature. Because, of course, what they really are is calls for propaganda to subvert and rebel against that other guy over there -- and the call usually has a neat laundry list of what you are to rebel against, and if you do not obey it, you are not rebellious -- or so it says. (The hypocrisy of saying that which toes the line is rebellious and that which does not is not -- well, it's funny at first, but it wears off very quickly.)
For some reason, I've run across a number of calls for this in steampunk. Prescriptions, in fact, that the "punk" suffix means rebellion and if you don't rebel against certain social structure, you aren't doing steampunk. More arguable than most claims, but there is such a thing as semantic drift. The number of fairy tales with actual fairies in them is vanishingly small. And while generally I have sympathies with trying to preserve a meaning, I don't think limiting the views that steampunk can express actually benefit the genre.