While her story world is dystopian and the author biography on the back cover states that Dunnion "frequently worries about the future," her novel does not conform neatly to either critic's generalizations concerning the YASF genre, although in a general sense Big Big Sky does fulfill many of their expectations.
Mendlesohn complains throughout her book that many YASF novels are not in fact SF by her definition, and Big Big Sky is perhaps only SF in its trappings.
Dunnion's novel thus fulfills the expectations of Applebaum and Mendlesohn, but not entirely--which is likely the case for any YASF novel when examined closely.
Bernard Beckett's Genesis offers another YASF dystopia, one in which the future island society of Plato's Republic isolates itself from the outside world.
Perhaps YASF suffers from the same pessimism of adult SF on a number of fronts: certainly, optimism regarding the rise of AI constitutes a radical stance of sorts, given the legacy of SF novels like Arthur C.
We might wonder why either Applebaum or Mendlesohn cares about YASF at all, if both consider it a flawed genre.
If YASF is a genre, with actual literary qualities shared between books, then it is to the books we must look, not to marketing departments, when determining what is and is not YASF.