This is a small community...many of the people here have "known" each other for several years...also keep in mind that many of the frequent forum posters chat with each other outside of the forums via teamspeak and the like...
That it is small and has an "everyone knows everyone" sort of environment lends to a lot of trolling, sarcasm, inside jokes, and the like...
There also are some rivalries between individuals on these forums that go back many months or even years...some of them are silly, some of them are just for fun, and some are serious spite that is well justified as far as the partakers are concerned...
Some of the same people who tend to troll or incite are also giving valuable feedback or providing legitimate advice/help...while there are some people on these forums that I tend to disagree with or get annoyed by, I've found that even the worst of the worst have valuable things worth listening too...
Another thing to always keep in mind is that SD listens...the comments and suggestions by people on the forums can actually affect updates and serious balance changes to the game...SD does not have a "knack" for game balance and heavily depends on the community for feedback...as such, if lots of people are providing the same wrong suggestion or wrong advice, it can adversely effect the future development of sins...
It can be frustrating or annoying when people harshly critique your ideas or opinions...but as the saying goes, the "squeaky wheel gets the grease" even if such advice or suggestions will not improve the game...if a million noobs advocate for a balance change that is completely fallacious and wrong-headed, can you really blame the handful of skilled players for doing everything they can to prevent such ignorant feedback from adversely affecting future game updates? On the surface it seems arrogant and egotistical to act in such a manner...but I'd rather listen to egotistical trolls all day than see SD adopt awful suggestions for "improving' game balance...
I won't defend the actions of the entire community nor will I claim there is no room for improvement, but being a forum member here is a choice...no one is getting paid to provide feedback for this game, write well-written posts, or act like a "mature adult" all the time...on one hand I wish some parts of the community were nicer...but on the other hand, I can't blame them for acting the way they do...