Personally, I think the big issue of doing a full Forgotten Realms Campaign Setting is that Faerun is really just
too big.
To try and encapsulate every single area of Faerun in a single book while also adding in all the stuff that players who don't care about the gazeteer stuff would maybe want (PC stuff, monsters, magic items etc.)... it means that each of the areas for the gazeteer can only get like a half-page to a page at most. And we're talking
entire nations that have to try and be condensed down to that size. And does that really help anyone run their games, when they have to try and figure out what is so great about running a campaign set in the Dalelands when each of the 14(?) individual Dalelands would get only a like a couple paragraphs each?
Yes... the players who are more interested purely in the grand history of the Realms I'm sure would cherish even a few paragraphs of "up to date" information as to what happening in those 14 dales... but if those paragraphs don't really help most players run and play their game... WotC seems disinclined to do it. Especially considering there are already several products that have been written specifically about the Dalelands (
Volo's Guide to the Dalelands;
FRS1 The Dalelands) that can and do give more useful information about what makes the Dalelands special than anything that could be put in a full FRCS. Yes... the information within isn't "up to date" as of 1491, but if you don't care about Realms history then it doesn't matter that the info in those products is "old". You can use it to create a current campaign for whenever you set it, because you wouldn't know any difference in comparison anyway. And if you ARE a historian and know what Faerun has gone through and experienced in the century+ between 2E and 5E Realms... you probably can take the 2E Dalelands info and "update" it yourself. Any mention of the Netherese? Remove it. Elminster can be found by PCs sitting peacefully in his tower? Remove it. A bit of evidence of the Abeil-Toril merge and separation? Add it.
But of course... as I've pointed out in previous posts about this subject... there's a small segment of the populace here that needs things to be "real". And the only way they can be "real" is if the half-dozen writers at Wizards of the Coast (and the several dozen freelancers they bring in to assist) make up, type down, and print up the couple paragraphs of things that have "happened" in the Dalelands. That's what's important and necessary to them, even if it is almost completely useless as an actual gaming product. And they need WotC to do this for them, even if it makes no real publishing sense.
I've said it before... but at this point, I sincerely believe that the folks at WotC think that an entire Forgotten Realms Campaign Setting book is not helpful as a
gaming product. History book? Sure, kinda. But helpful for most people to run a game? Not in the least. So they aren't going to write one. Not on that scale. They aren't historians, they are game designers. So instead, they are going to let people like Ed Greenwood take a section like the Border Kingdoms and flesh that part out... they'll let Adventurer's League tackle the Moonshae Isles and the Moonsea... and if they find a gaming product or adventure they want to write that involves a location that could be updated (Cormyr, Thay, Mulhorand) then and only then will they do it themselves.
This is what I said back in 2014 when 5E started... and this is what I will continue to say and believe until WotC proves me wrong.