So I think the want vs need does apply here and the Morello post is true in that regard though it's just common knowledge. As for the rest I think it's more about room for progress than about exclusivity, but what do I know
I don't even strictly disagree with what he's saying.
What I am disagreeing with is the notion that WoW's "downfall" is often solely related to the removal of exclusive content when in reality, there have been quite a few factors that caused the decline in subscriptions. Him claiming that keeping exclusive content in the game would've changed that is just ignorant. Ignorant in the most literal sense of the word, as Morello (as so many forum users) just chooses to ignore the circumstances under which WoW is operating that have changed dramatically.
I mean, let's say you switched from a Chevy to a Ford. The Ford was stolen in front of your house. Do you ignore the fact that your Chevy was locked 100% of the time when it was parked whereas you never locked your Ford? Would it mean that Chevy's cars are generally harder to steal? No, it wouldn't. You couldn't form any sort of conclusion about whether Chevys or Fords are harder to steal when you left one unlocked and the other one locked.
Leaving out very important stuff like this in any debate would make the person in question look a bit questionable in my book.