Who knows whether these theories are true or not. But Sasuke IS coming back. The last page on mangastream says Sasuke's Homecoming. Kishi is definitely building to a happy ending one way or another. Even if he was truly gone for 12 years, does that mean everyone can't be happy and fullfilled when he returns? Kishi has given FAR more tragic plotlines than that.
yeah, to put things frankly no one can portray their relationship other than the author himself because Sasuke and Sakura’s always is the most unpredictable, it’s a roller coaster ride.
all the other ships that did became canon had their spotlight in the Hiden series, though all of them are a fluff fest, this one is surely going to be one hell of a story because it’s Kishimoto who is writing it, not other author.