Well, the vocal minority trashes Skyrim, and majority praises. If it is a matter of voting who is right, minority looses. I really do not like any GTA game, any Halo game, and any sport sim, I find them exceptionally boring, but it does not mean that all of them are trash. Also I found it a bad policy to root for some game by trashing its competitors. Let's just wait for trailers, gameplay videos, and such, ok?
I partially agree with your views on this, in that I agree that it's wrong to say "I hate Game X therefore Game X is trash". Yes, some games ARE just trash, but in most cases it just means that the game isn't to your personal taste.
But regarding the views on Skyrim expressed in this forum (and, earlier, the views on DA2), a large part of it is simply that the views of the forum members don't necessarily reflect the gaming world overall, nor should they. This is a subset - "People who like The Witcher Games". So yes, there are probably more people here who dislike Skyrim than in other forums, more people who prefer OTS view to first-person, more people who prefer story-driven to free-form, more people who prefer single-player to multi-player. It isn't because they feel a need to support CDPR, it's because that preference brought them here in the first place.
And yes, that naturally also leads to some concern (and occasional over-reaction) when we hear something that makes us wonder whether TW3 will follow those preferences. Given the limited amount of information available, the trust we have in CDPR does become important.
And negative feedback is just as important as positive feedback. Only listening to fanboys doesn't help any developer.