Where is SFF headed? I think we're going to continue to see more stories rooted in non-western cultures. I think we're going to see more robust casts where the straight white guy is the token (and not as the Great White Savior). I don't think diverse stories are a passing fad, rather they're a change in consumer demand encouraged by Hollywood making consumers aware that representative entertainment is available to the mainstream.
I think as long as real-world politics is shit, that'll the demand for HEA in SFF is going to increase; that includes breaking grimdark's stranglehold on the bestseller lists and waning popularity of irredeemable anti-heroes. I think there will be an uptick in mass-anarchy themes, where the quests change a nation rather than bestow individual glory. I also think humorists are going to come back to SFF to shine a shaming light on the corruption and frustrations of the real world.
I'm looking forward to all of it, as a reader and a writer.