Ouch. This whole "Abyssal Plague" story sounds like the kind of thing I used to enjoy as a 12-years old young nerd. Now I wish I had never learned about its existence. Ignorance is bliss, after all.
Keep in mind that the Abyssal Plague was for 4th edition. Personally I would have been more excited if it referred to the spilling over Blood War, but whatever.
Actually, there were some decent parts of the FR novels that related to the AP, but... no, wait... that was something else
My main point was that the FR has certainly been a "dumping ground" for shoehorning elements into the setting for, well, for a long, long time. To start complaining about that *now* seems like a foolish conceit. And while there are other settings that have stronger elements of "X", that doesn't mean that those things aren't also canon in the FR. Everyone knows that Dragonlance was the setting for Dragons and lances, but Dragons are everywhere in Realmslore, even riding them into battle. Ditto for Ravenloft and Vampires, Greyhawk and liches, Ebberon and, er, maybe not Warforged per se, but automations are there, and there are probably a few on the gnomish island of Lantan. And I'm not even talking about the barbarian Steppes where there are [Mongols] or the Chult Peninsula [dinosaurs], or Mazteca [Aztecs], or Kara-Tur [Oriental everything, including the "Great Wall"], or Zakhara [Arabic everything], or Mulhorand [Egyptian]. They might not be the most popular places to visit, but they exist and *have existed* in the Realms since at least 2nd Edition.
What I am most interested in is the story, the area, the tie-ins, and the immersion factor. If they do those correctly, then IDC if you're a die-hard fan of whatever setting, you'll happily play the adventure and make it yours. Or, steal all the ideas for it and make that yours, or port the story to your favorite world. Whatever. Good adventures > badly written adventures, period.