I think the idea that WotC hates Greyhawk and has been trying to kill it off is ludicrous. If anything, Greyhawk under 3e has never been more than a spice that WotC has used when they needed
something other than Generic Fantasy Land X(tm). It seems clear to me that WotC used Greyhawk whenever they needed some place names or deities to refer to in flavor-text, but that was the sum total of 'official' support. This was not done out of malice, any more than it was in the AD&D DMG or PHB. If you didn't know who Vecna or Otiluke were, it didn't effect that much, per se.
Under 3e, there have been only three real Greyhawk products of note:
- Living Greyhawk Gazeeter (and it's 'player' version)
- Return to the Temple of Elemental Evil
- Expedition to Castle Greyhawk
The LGG was a black and white soft-bound printing, had very little art and was almost entirely fluff. While it contained lots of good information, it was dry and was more for people who were already Greyhawk fans. It did not have enough space to really flesh out the setting or its history and was meant more for Living Greyhawk players than it was for the D&D community at large. It was far outshined by the release of the Forgotten Realms Campaign Setting (note those last two words, that's a critical difference), an all color, high-glossy hardback printing that was dense with content, including new spells, classes, races and unique mechanics for the setting. I bought it, and I had no intention of using the setting. It's an attractive, well-made and very useful book. The LGG had nothing like that. It was exactly what it said: about five pages of history and then a listing of every country with some details about it's cities, towns and a few tidbits. What's there is good, but it's bare-bones. You got a LOT more for only, what? $12 dollars more?
RtToEE was the crowning glory for Greyhawk. Truly set IN Greyhawk, it could still be fairly generic if it wanted to be....but overall, it was strongly tied to the setting. Compare this with say, The Standing Stone. According to Hobo, the Standing Stone is a Greyhawk module, because one of the NPCs shares a rumor about Verbobonc and another mentions Pelor. I respectfully disagree. While there is nothing in the original Adventure Path that prevents the modules from being set in Greyhawk, neither is there any compelling material to force them there, either. Compare that with ANY Eberron module or City of the Spider Queen, which require significant retooling to use outside of their core setting. Mind you, that's part and parcel of Greyhawk (it is, after all, the setting that D&D was built with)...which is again, why WotC chose to use it more often than not, when they needed
something.
Now, there are some books that I think Hobo would be justified in saying supported Greyhawk, if not entirely actively. Deities & Demigods (to date, my vote for most disappointing supplement) had decent Greyhawk support (limited though it was). Some books certainly used place names or deity names in Prestige Classes, such as the Temple Raider of Olidamarra. Greyhawk was certainly not left entirely in the cold, just not really strongly supported. A large part of this effort came from Erik Mona and Lisa Stevens' efforts, to be sure.
Probably some of the best Greyhawk material wasn't actually seen by many folks...it was the Living Greyhawk material done by WotC for the LG magazine which eventually merged with Polyhedron and then was absorbed into Dragon magazine. Once again, here's where WotC allowed a LOT of Greyhawk material to be produced: both Dragon and Dungeon, in their final couple of years, featured a ton of Greyhawk content. Stats for famous Greyhawk NPCs, modules in Dungeon and even mini-campaign settings like the City of Shadows. More than once, some WotC staffers implied that, by default, anything that wasn't specified was consider Greyhawk to them. And don't forget the series of Greyhawk novels WotC released a few years ago, too.
So while WotC didn't support the setting as rigorously as FR, it's disingenuous to say that they did it dirt. Clearly, WotC didn't see the same return on RtToEE that they did on some publications...especially as the Greyhawk fanbase has suffered a pretty noticable split over the years. It's been my perception that the FR fanbase didn't splinter as significantly over something like the Time of Troubles in the same way. And yes, the FR fans buy the novels. Greyhawk's novels clearly didn't sell nearly as well.
Honestly, if I wanted anything from WotC, I'd rather have just one big Campaign Setting book, like Eberron and the Realms have gotten. But I can understand why they're not supporting it, and it doesn't exactly break my heart.