Eh, I'll be honest, I find "traditional Faerun" beyond the Sword Coast unlikely, especially as how Ed Greenwood has been working with other creators to make books like the Border Kingdoms and the Zhentarim Keep book on the DMsGuild. The pattern with these new setting books has been to explore unique niches of D&D to push different themes and styles of play; I would say every book from Eberron onwards has been in that model. And Faerun is just "more traditional D&D." I don't think that's a bad thing (the primary game I DM is Forgotten Realms), but it doesn't match 5E's Setting design philosophy to publish the Faerun Setting Book.
Planescape, Dark Sun, and I believe Dragonlance do hit far more unique niches than Faerun does. Planescape/Dark Sun speak for themselves (you yourself think they're coming so I don't need to explain). But Dragonlance is more unique than Faerun due to it being a war story, akin to the War of the Ring; there are major forces on the move, and you the heroes need to save the day from the forces of evil taking over the world. A setting that is explicitly set in an epic conflict has not really been tackled in 5E, and is a better niche and more likely publish target than Faerun in my mind.
Additionally, the "setting revisit" that Ray mentioned was actually in 2020's "Future of D&D Panel." The revisit was not mentioned again this year. So I think whatever that was is actually shelved in development.