So what? It was 3rd edition already. And as others have pointed out, what that Ed-dude says is moot. At best, he's now a co-designers for the Forgotten Realms, since the day he sold his intellectual property to other guys. Meh, Eberron only makes sense for D&D 3rd edition, as it's the only campaign setting where they intelligently applied most of the magic rules to a world, unlike the crudely stitched Forgotten Realms. The Forgotten Realms just are more the effort to be redone than Eberron, because people played Baldur's Gate and perhaps also Icewind Dale enough to become D&D-pen-and-paper-players. All that Eberron has to show is the lame-o-game D&D Online. It's all about name-recognition and brands.
That's why they said that 100 years pass, so people like you should feel happy, because it "evolved" to the new face it gets (hur hur hur hur

). That spellplague stupidness is as idiotic as the Times of Troubles, and it changes the setting to accomodate the rules better. And it's so that the new demographic still see, hey, that's the world where that Baldur's Gate-city is located, that's cool, I can now play in that world too with my ranger-barbarian who's got a miniature giant pet hamster from space, and all that other whacky shenanigans.