Many giants fall. The biggest problem is the ability of the new, small companies to get noticed by the buyers. Far too many people get excited when they hear about the latest title from their favorite company, and far too many people don't even give the newcomers a chance because they don't recognize the game.
Furthermore, far too many people get excited by the big production visuals and not the actual substance of the game (you see this a lot with movies too). And that is not a realm where the newcomer can compete.
Oh, some exceptions pop up from time to time, but, as a rule, people are too beholden to their corporate favorites. Just try saying something good or bad about Apple, and you can see the loyalists run in to defend or attack. The corporations love your loyalty, but will not reward you...they just keep counting on it.
You want change? The only path to change in a marketplace is to vote with your pocketbook.
Not thrilled by WoD? Know that Blizz can do better? Stop your subscription. There is no other answer.