Chaosmancer
Legend
Humans get like 300 gods in D&D, but we're supposed to believe that all orcs are slavishly devoted to one or two. I have some issues with that.
No earlier edition tied monstrous humanoids so closely to gods in a core rulebook (unless, again, 4e did, which just means the silliness began a little earlier than I thought).
I've never heard anything except good things about Eberron. It is something I've often thought about looking deeper into.
As for the above...
There are so many weird things about official DnD religious lore. I never played 3.X but those were the first books I ever cracked open.
Looking through them, Moradin was the God of the Dwarves. All Dwarves, all aspects of Dwarvishness, if it was about Dwarves, Moradin was in charge of it. Same with Corellon Larethian, Gruumsh, or Garl Glittergold. They were it according to the book.
Then you have the generic dieties Boccob, Pelor, Kord, Fharlanghn, ect. All listed as the God of (insert thing here).
There are zero listed human deities. I remember 4e being the same way.
5th edition is the same too, but there was this little sidebar in the phb that mentioned there may possibly be other dieties. It took google and wikipedia for me to start hearing about whole other pantheons. I figure they had to exist before, probably in an old splat book, but even with what I found... there wasn't much to find.
It feels like playing a game set during the Rise of Rome, and the game saying the Romans worship the God Jupiter and left it at that. There is a lot more to find, a lot more interesting stuff to dig into.
I don't mind Volo digging more into some of this, bring the monstrous deities to the fore so we can at least see what they look like, and maybe give us more than a blurb. Tying them to their deities seems more helpful than harmful to me, because from a very religious society we can infer a lot of culture and motivations.
Or at least, that's what I've been thinking as I've seen people talking about this. Still don't have my copy of the book, so it might have been handled poorly. I already know I'm going to need a lot of mental rewriting for the Yuan-Ti, because the idea that a society would name their lowest and least respected members "PureBloods" and their highest ranked and most respected members "Abominations" is a little hard for me to swallow.