Ruin Explorer
Legend
You say that like it isn't a selling point. As just established, the Sword Coast is a big advantage for WotC publishing strategy precisely due to the generic nature of the region. The 3E FRCS had tons of material on the Dalelands, because it was the core of Greenwood's campaign.
I basically agree.
But the Dalelands, specifically, is too similar to the Sword Coast in pretty much all ways. Culture is similar (especially for adventurers), vibe is similar, terrain is similar (temperate and hilly instead of temperate and coastal). Yeah, there are differences, but the broad vibe is very close. It's like Cascadia vs the SC's North California or something.
It would have made an excellent first book for the 5E Realms.
As the SC book exists I would say going further afield would make sense. Other areas could provide sufficiently broad appeal I think! Though not Cormyr never Cormyr!