The reason, I think, is because games like Elemental only come along once in a blue moon. They are extremely rare, and the people interested in these kind of games wait years and years hopeful of the next one to come along.
First-person shooters, platformers, and even real-time strategy games are a dime a dozen. Rarely does a week go by that you don't see another one of these kind of games. If one doesn't live up to expections, we only need to await a short time until another one is released.
Everyone on these forums are fans of the genre and I think just about every one of us was really looking forward to Elemental. When it was released, we fell into two camps: angry disappointment, and undying loyalty. We're all dealing with it in a different way, and it is so extreme because of the high expectations we all have had.
Many of us still do not want have to admit that we waited all those years for bitter disappointment, we are willing to lie a bit to ourselves to keep hope alive and to feel like we have not wasted our money and time. Others have come to a reality that their dream was broken, and are bitter about it.