The most vocal critics here are typically those who most love Disney. That's precisely why they bother to expend so much time and energy discussing the product: they hope that, in some small way, what they say here can inspire those in charge of the product to undertake positive change that will make the product more worthy of everyone's patronage in the future.
I've never understood the idea that those who say anything that's at all negative about the parks must not care for them or must find them valueless.
Take movie critics as an example: you'd have to truly love movies to be a movie critic, yet critics provide negative criticism of movies every day -- sometimes criticism that comes across as harsh. Implicit in the critic's job is the aspiration that, by providing guidance to the public about what movies are worthy of their money, quality products are rewarded with patronage, and inferior products are not. In theory, this would encourage studios to produce more quality movies, enriching the market for everyone who appreciates watching them.
On a message board like this one, everyone is -- to some degree -- an amateur critic who seeks to effect positive change. Someone who doesn't care for WDW and other Disney parks is not going to waste time posting here when there are countless other things in the world to occupy their attention.
I find posts that provide constructive criticism to offer a far greater contribution to meaningful discussion than posts whose content suggests that Disney is infallible and that its products should never be considered with any substantive discernment.