The two Hugo nominees that were most obviously SFF stories (The Water That Falls On You From Nowhere and The Ink Readers of Doi Saket) did nothing for me (and I'd argue that TWTFOYFN could be almost the same story without the fantasy/absurdist element), whereas the two that some people claim aren't really SFF at all (Selkie Stories are for Losers and If You Were a Dinosaur, My Love) seem far superior to me.
Over on the IYWADML thread, I asserted vehemently that it was speculative fiction. The same goes for SSAFL.
It's true that the poem says IF this speculative thing were so, rather than IT IS, and it's true that Selkie Stories' protagonist never actually saw her mom change into a seal and swim away, so technically she could just be constructing an illusory worldview that lets her transform the inexplicability of loss and heartache into the inexplicability of magic. However, isn't the element of uncertainty integral to speculative fiction? Maybe even the uncertainty of our definitions, and where we draw the lines? So, even if a protagonist KNOWS that she's just building castles in the air, I'm enchanted to be invited to lend a figurative hand with my suspension of disbelief, especially when the writing is beautiful and/or the character is well drawn.
What's the opposite of speculative -- mundane? As far as I'm concerned, these two stories are not the least bit mundane, in either sense of the word -- neither too worldly and un-speculative for inclusion here, nor too dull or lacking in interest and excitement. The conflicts may be internal, and the speculative elements may be primarily in the protagonists' heads, but in my opinion, that makes them no less worthy of our attention and discussion.