saying simply "this is stupid, get off the forum.", or "suggestions never get implemented.", or something like that really doesn't help progress the development of DF, forum goers have fixed several critical bugs in DF, even code related ones, and have actually been a driving force in many subtle ways to DF's development.
so please, think before you post.
On the other hand, everyone who joins the forums has a creative brainstorm for at least their first month posting here. Pretty much without fail. Some people never stop having brainstorms, they post a new suggestion every week.
When people fall too deeply in love with their own ideas, and stop distinguishing the game and their own ideas, that's what I think gets older forum members hackles up.
I rarely see veteran forums members telling people to shut up, or that their idea is stupid. They DO routinely ask people to put things in the right places though, instead of trying to put their personal issue front and center so they can get the best chance of a response from Toady. That does get pretty annoying, especially when you've seen that behavior repeated for years. And when you stop and consider what was actually said that touched off this debate....it was literally just a link to the right place. It may have been terse, but that's all it was.
So personally, I think creative types need to be just as careful about associating their own ideas too closely with the game, or getting too defensive about it. Because for all the subtle effects our suggestions have on the game, they are simply that at the end of the day. Suggestions that Toady can take or leave. Treating them as more than that is trying to step over the line between player and developer, or asserting you have the right to. And that will eventually annoy someone.